Talk:Machine/Archive 1

Archive 1

Archive 2

Machines vs other kinds of devices

It'd be nice to see the table separate machines from other sorts of devices. Again, IMO, machines have rigid moving parts. A ramjet combustion chamber is a device, but not a machine in and of itself. To be a machine it needs pumps and stuff attached to feed the fuel. Neither is a rope, an airfoil, a sustained nuclear reaction, or a single gear a machine. Maybe the whole table should be moved to the device article. --kop 04:43, 14 April 2007 (UTC)

Buildings as machines

Isn't i also possible to incorporate other views of "machines".love It is a famous thought among a lot of architects to look upon buildings as machines. But what do they mean? What does this machinery consist of? What makes it a machine?

Nothing. That was just Le Corbusier summing up (one aspect of) the post-modernist view of architecture. --Heron 17:06, 3 December 2005 (UTC)

Le Corbusier was speaking metaphorically. A building does not generally fit the definition of a device that transforms energy. A building contains many machines - so I suppose you could wedge it in if you had to. SteveBaker 17:09, 21 November 2006 (UTC)

Buildings and bridges and other large structures do have moving parts, and sometimes, some of those moving parts actually are intended to transform energy. Some extremely tall buildings and some bridges have mechanical systems that are intended to dampen oscillations caused by wind, earthquakes, etc. Those dampers are designed to transform the mechanical energy of oscillations into heat energy.

Other moving parts include bearings that relieve strain as structural components expand and contract due to changes in temperature. Here in Pittsburgh, PA, USA, we had a bridge fail on a particularly cold night in March 2008 because a bearing locked up (lack of maintainence, most likely). The bearing failed to move, and so one end of the span slipped off of its supporting structure when the span contracted. (FWIW, It only dropped a few inches. Engineers were able to raise it back into place with no major damage done.) 192.55.12.36 (talk) 18:21, 12 March 2008 (UTC)

See Tuned_mass_damper#Examples_of_buildings_and_structures_with_tuned_mass_dampers 192.55.12.36 (talk) 18:27, 12 March 2008 (UTC)

A computer is a machine

The Longman diction defined a machine as "a man-made instrument or apparatus that uses power"; the Collins cobuild dictionary says it is "... a piece of equipment which uses electricity or an engine in order to do a particular kind of work." The OED, being based on historical principles gives definitions dating from the 1500 & 1600s; the world has moved on since then.

Computer people call computers machines and a variety of computing terms are defined in terms of machine, eg programming language and machine code.

Those of you who argue that moving parts are needed for something to be called a machine. Analog computers are obviously mechanical in nature. But what is a moving part? Computer memory operates by storing packages of electron charge, cpus operate by changes in electronic state. Are electrons, collections or otherwise, not moving parts?

Excluding computers from the definition of machine is obviously incorrect. Derek farn (talk) 00:36, 5 August 2008 (UTC)

Concur with Derek farn here. The traditional mechanical sense of machine should definitely be emphasized in this article, but we shouldn't exclude "computing machines" from the definition or article. Nowadays, that latter sense is almost as widely used as the odler "transforming forces" sense. LotLE×talk 00:48, 5 August 2008 (UTC)

Electric Motors

How can the electric motor be left out!? It would fit the bill a lot easier than a transistor. ~RayLast ^«Talk!» 21:50, 13 February 2008 (UTC)

An electric motor is a transducer not a machine; it converts electrical energy into mechanical energy. It can't do work unless connected to other components. Similarly a battery isn't a machine (converts chemical energy into electrical energy). A transistor on the other hand is not a transducer; it controls or modifies electrical signals acting as a switch or an amplifier - some engineers say that's esentially the same thing. If electronic circuits are machines (I say they are; some hold to the classic definition and say they aren't), then transistors are machines.

Cheers, Rico402 (talk) 08:57, 5 August 2008 (UTC)

Moving parts

IMO a machine must have moving parts, in the "commonly accepted" view of a machine. A wheel and axel is a machine because the axel turns in a bearing. Whereas an inclined plane (one of the examples of a simple machine) may as well be a naturally occuring hill. One could say that a constructed inclined plane is a tool, but not a machine. Likewise an atlatl, or a hammer for that matter, are not a machines even though they both accomplish work. They are tools. So, I'm fiddling with the introduction. --kop 04:06, 14 April 2007 (UTC)

You're messing with the "simple machines", which are the basis for all (non-electronic) machines. The simple machines are defined by their ability to provide mechanical advantage, not "accomplish work", e.g. a lever increases force in proportion to the difference in length on either side of the fulcrum. The capacity to do (accomplish) work is energy. Machines and tools require energy to do work, otherwise they haven't the capacity. A hammer (with a handle, not a rock in your hand, that's just a tool) is an extension of the arm and hand - the same principal as the lever; likewise an atlatl; they're both (simple) machines as well as tools.

As far as "an inclined plane ... may as well be a naturally occurring hill"; keep in mind that you have to find a hill with the right slope to move a heavy load vertically with the force available. (As no doubt you already know, force is not equivalent to energy. Force over a distance equals work, F x D = W; and work is equivalent to energy, i.e. it takes energy to do work, and the units, joules, are the same. Btw, the article on joule is a bit off - the fist paragraph anyway.)

Moving parts: The load on an inclined plane is in motion, so that's the moving part. An inclined plane and a length of rope would constitute a machine by your definition. (Technically the plane is in relative motion with respect to the load. But that's a stretch.)

Cheers, Rico402 (talk) 10:41, 5 August 2008 (UTC)

References

How about providing some references for Types of machines and other devices and Machines in Education and Art so the "original research or unverified claims" tag can be removed.

Cheers, Rico402 (talk) 06:53, 6 August 2008 (UTC)

"A 'machine' is any device that uses energy to perform some activity."

Not quite. The heating element on an electric stove uses energy to perform "cooking", arguably an "activity", yet a heating element is a transducer for converting electrical energy into heat energy, not a machine. Similarly, electric motors are transducers for converting electrical energy into mechanical energy. The spinning shaft of a motor is pretty active, but unless connected to a machine it can do no work. A cone-type loudspeaker however is a linear motor that indeed does work; while applying a force over a distance - the classical definition of work - it compresses and rarefies the air on either side of the cone.

I would say that the heating element of an electric stove is a simple machine, an electric motor is a machine in the same sense that an internal combustion engine is a machine and not a simple machine. We need to get away from this nineteenth century view of "rigid bodies". The article also needs to be differentiated from the one on simple machines, so the examples need to be mainly non-simple machines. Derek farn (talk) 09:54, 6 August 2008 (UTC)

I'm going to re-write the intro with references.

Cheers, Rico402 (talk) 01:28, 6 August 2008 (UTC)

The simple machines need only a brief mention, but since they are the basis for the more complex machines we shouldn't leave then out entirely. I have no problem with deleting the list from the first paragraph, since there's a link and they appear below.

But your definition is incorrect and you cite no references; that's not acceptable. Heating elements, light bulbs, batteries, photovoltaic cells AND electric motors ("actuators") are transducers, not machines - they do no work, that's a very important distinction. The CEofS&T article on the internal combustion engines doesn't call it a machine, but "a prime mover"; the article runs half a page without once using the word "machine". Although an ICE employs many simple machines, technically it's not as a whole a machine, but a source of rotationary energy. (It's not list under "Types of transducers".) This may sound counter-intuitive, but nonetheless it's correct. However it seems a gray area, which is why I kept it in as a courtesy. (But why did you edit out the operational details?! I specifically outlined the moving parts at the heart of the system to slip it in under the machine definition.)

Machines and the sources of energy that drive them fall into separate categories that we maintain for very sound reasons, not just semantic whim. I suggest you bone up on you physics and engineering. We have a hard enough time getting "computing machines" into the mix.

Instead of "perform some activity" (vague and incorrect), try "alters or transmits applied forces to do work." (Technically it's "useful work", but I think we can survive without that bit.) That phrase can be referenced to The AHD

Cheers, Rico402 (talk) 12:52, 6 August 2008 (UTC)

If work is crucial to the definition of a machine (I'm not certain that it is), then we need to agree on a definition. We have Mechanical work and Work (thermodynamics), perhaps there are others, the work page does not list any others that look relevant. What is your argument for showing that a transducer is not a machine? It certainly fits within the attributes of a simple machine. What is you definition of work (in a sense the definition chosen selects what is and is not a machine)?

With regard to CEofS&T article not mentioning that an internal combustion engine was a machine, perhaps they thought it too obvious to mention. Does the article state that such engines are made of metal (another obvious statement)?

I don't see a universal connection between applied force and something being a machine. I hope we agree that the human body is a machine, where is the applied force that operates this machine? Does the work have to be useful? Ok, you are using the term useful work in a technical sense, but I suspect that most readers will apply the common meaning of useful (I can think of a device that is a machine and does useless work) and be unaware of its technical usage. Derek farn (talk) 19:24, 6 August 2008 (UTC)

Ok... back from hiatus. Hmm... If my comments above seem to suggest I'm arguing that an internal combustion engine (ICE) is not machine, then I've expressed myself rather poorly. (Which on review seems to be the case. Shame on me for not reviewing my own work.) My point was that an ICE is a machine for converting chemical energy into mechanical energy. The output of an ICE is mechanical energy, hence the "not as a whole a machine" comment. (A "prime mover" by the way is a device that transforms heat or pressure into mechanical energy.) ICEs aren't defined to be made of metal; they happen to be (mostly) made of metal because that's what our present technology can economically produce that meets their physical requirements. I can easily imagine ICEs made of composite material, perhaps coated with Teflon or some other suitable polymer.

Since this is an article for an encyclopedia, not a two-line entry in a dictionary, I see no problem with exploring both the "classical" and modern meanings of the term "machine", as well as the colloquial (informal) usage of the term. The "useful work" referred to in the "classical definition" - resistant bodies, moving parts, etc. - would be mechanical work.

Furthermore, I feel the article should inform the reader of the various meanings of the term machine, and examples thereof, rather than simply reiterating what "most readers will apply". If that were the case, there would be no need for the article. Readers deserve formal definitions and explanations supported by authoritative sources and adhered to by physicists, mechanical engineers, electrical/electronic engineers, computer scientists, etc.

Useful work? Well that's a crucial part of the classical definition. For example, odd as it may seem, a mechanical clock is not a machine in the classical sense because it does no "useful work" - defined as applying a force over a distance. Is the human body as a "machine"? In the modern - and I suppose informal - context, not only the body, but molecular mechanisms within its cells are referred to as machines. There are innumerable examples of biological machines.

My primary concern here is that you seem to want a simple, succinct explanation of what constitutes a machine, and I'm just suggesting that that's not enough. By all means we should explore the modern understanding of the term, but let's not neglect the historical context just because we apply the term so much more broadly than as it was initially conceived hundreds of years ago.

Anyway, nice chat; you make some interesting and valid points. I'm considering expanding the article - incprorporating some of the things we've discussed here, and making sure it is all supported by authoritative sources - and posting here in "Talk". If we can agree on the content, then it can be uploaded to the article page. When, if ever, I get around to that I can't say. I'm behind as it is on some articles I've promised to work on.

Cheers, Rico402 (talk) 13:45, 4 September 2008 (UTC)

What is a moving part?

What is a moving part? Electronic computers operate by controlling the flow of electrons. Some people might consider these to be moving parts. I am not that taken by the term groups of atoms, but don't see what else to call a moving part. What term would you suggest? Derek farn (talk) 10:40, 14 September 2008 (UTC)

Good question. I thought I made it clear - but perhaps not - that the phrase "moving parts" is used only in reference to the classical concept of a machine, as in classical mechanics, which doesn't include electrical circuits or the behavior of electrons. In other words, the "moving parts" are by definition "rigid or resistant bodies".

The article does not make any distinction between classical and non-classical concepts. Perhaps it ought to, but at the moment reads cannot be assumed to have this reference point. Derek farn (talk) 17:21, 16 September 2008 (UTC)

Even under a rather broad, modern concept of a machine, electrons should not be considered "moving parts". That would essentially be mixing classical and quantum mechanics - not a good idea for a general audience. And electrons are not "rigid or resistant bodies", they're considered "point particles", that is, they have no volume (that we can detect). They interact with one another and other particles according to electrostatic principles.

Your quantum mechanics argument is a red herring. There are many situations where electrons can be treated according to classical mechanics and there are situations where atoms and groups of atoms must be treated according to quantum mechanics. Electrons might be idealised as point particles or as non-point particles, it depends on the situation being modeled. Atoms also interact according to electrostatic principles, after all the sharing of electrons is what holds molecules together. Derek farn (talk) 17:21, 16 September 2008 (UTC)

Anyway, I think it would be best to make a distinction in the intro between the classical and modern (or common) usage of the term "machine" - seems we're only confusing the reader if we don't differentiate between the two early on. (Or is it three, or four?? I've lost track. :)

For what it's worth, electron's have a "work function" expressed in electronvolts that has to do with it's movement from within to immediately outside a solid (electrons exiting the cathode of a vacuum tube, for example, have a "thermionic" work function), but this is unrelated to mechanical work - it's not electrons "pushing" against one another, and I don't think we need to delve into the minutiae of quantum mechanics and energy states to include electronic systems as machines; recent history and common usage should be sufficient, don't ya think? Electronic "computing machines" and all that... If we need a further explanation or a reference or two, I can probably come up with something. I think I'll look into whether anyone ever referred to wireless telegraphy or radio equipment as "machines". After all, the "electronic age" is generally considered to have begun with the introduction of the triode vacuum tube or "audion" - first used as a detector in wireless telegraphy (pretty sure).

With regard to electrons pushing against each other. It is electrical repulsion that pushes clumps of atoms (ie, moving parts) away from each other as they get closer together. Derek farn (talk) 17:21, 16 September 2008 (UTC)

Wow! Long answer to a simple question.

Cheers, Rico402 (talk) 12:15, 16 September 2008 (UTC)

I don't find any of your arguments convincing and in some cases they are technically incorrect. Derek farn (talk) 17:21, 16 September 2008 (UTC)

"Quantum mechanics is a red herring"??!! Quantum theory is crucial to the understanding of modern electronics. About the only "situations where electrons can be treated according to classical mechanics" is with respect to the Newtonian theory of gravity, since they have mass. But an electron's tiny mass is irrelevant in this regard because gravitation is so weak compared to electromagnetism (and the other fundamental forces). Whether an electron (or a photon or any elementary particle) actually has a physical size is irrelevant. What is relevant is that its size is too small for its behavior to be described according to the principles of classical mechanics. (Electrodynamics and electrostatics are disparate from classical mechanics.)

"With regard to electrons pushing against each other. It is electrical repulsion that pushes clumps of atoms (ie, moving parts) away from each other as they get closer together."

Your mixing apples and oranges; "clumps of atoms" don't go zipping about in electronic circuits. The electrostatic repulsion of which you write occurs between solid bodies, and is why such bodies don't just flow through one another; their constituent electrons repel one another. (And why a coffee cup doesn't just fall right through the table it's setting on.)

If you're try to argue that electrons are "moving parts" obeying the principles of classical mechanics, and therefore electronic circuits are machines in the classical sense, then you're way off the mark. Furthermore, it's unnecessary. Electronic computers (and perhaps other electronic devices) are machines in the modern sense - if at all - by common custom, not because they have "moving parts".

Rico402 (talk) 00:46, 18 September 2008 (UTC)

Article is inaccurate and lacks references

The first paragraph of this article is largely inaccurate as it stands, and cites no authoritative reference for the content other than for the etymology of the word "machine" (which I provided). In fact, this is the only reference cited, which is why the article is tagged "may contain original research or unverified claims".

Efforts to remedy the situation have been consistently resisted by Derek farn, whose ignorance of the subject is exposed in his comments in the above sections, "A 'machine' is any device that uses energy to perform some activity" and "What is a moving part?".

Apparently Derek farn believes a machine is whatever he says it is. (E.g., "the heating element of an electric stove is a simple machine" and "a transducer ... fits within the attributes of a simple machine"; both statements are patent nonsense.)

I have done my best to disabuse him of this conceit, but he refuses to accept established scientific and engineering nomenclature and principles as a suitable foundation for the content of this article. Thus far I have been extremely patient with regard to his obstinacy, but it has become quite clear that polite discourse will not resolve the matter.

In an attempt to reach a compromise, my last edit retained most of the previous content, but with the first paragraph rephrased and expanded in such a way as to make it more accurate and in general agreement with the references cited. (I would still judge it at least somewhat inaccurate.)

We don't know who or what Derek farn is, as his user page is blank, but I see he received a "last warning" from an editor for his "reverting habit and loose restatements".

My credentials can be viewed on my user page. If my next edit of this article - which will likely be a revert to my last edit - is again reverted by Derek farn, I will submit a Request for page protection.

Rico402 (talk) 02:56, 9 October 2008 (UTC)

Rico402 I would be happy to discuss any improvements to the article, but see no benefit in joining a slanging match. Derek farn (talk) 11:10, 9 October 2008 (UTC)

Biological 'machines' should be excluded

I strongly disagree with the concept of biological 'machines' and propose that all examples of such usage are by definition analogy or metaphor. If we accept that a machine is a device, which in turn is an "invention or contrivance" (Macquarie Dictionary, 2nd ed.), then a designer is necessary. Tacitly invoking 'intelligent design'(cf. evolution) hardly meets Wikipedia neutrality guidelines. Shythylacine (talk) 22:27, 21 October 2008 (UTC)

I agree that we should not invoke any form of intelligent design. However, I do think that some biological systems can be considered to be machines. So the problem is with use of the term 'device'; we need to use another word. Nothing springs to mind at the moment. Derek farn (talk) 12:32, 22 October 2008 (UTC)

No, the problem is with Derek farn. There is no problem with the term "device", except in the ignorant little mind of the aforementioned, who chooses to ignore the conventions of science and engineering in favor of his own prejudices, apparently pulling ideas out of thin air, as he can cite no references for his erroneous assertions, nor provide us with a resume of his qualifications on his user page. He continues to assert that a machine is whatever he says it is, lording his ignorance over and above the established scientific and engineering nomenclature.

"Biological machines" are disparate from the man-made mechanical and electrical contrivances formally defined as machines. Other suitable terms include contrivance, system, apparatus, mechanism, "collection of rigid or resistant bodies", etc. (Sources- Concise Encyclopedia of Science & Technology, Third Ed., Sybil P. Parker, ed., 1992; New Age Encyclopedia, Bicentennial Ed., 1975; McGraw-Hill Dictionary of Scientific and Technical Terms, 5th Ed., 1994; Amer. Heritage Dictionary, 2nd College Ed., 1985; Webster's New School and Office Dictionary, 1974; The New Amer. Roget's College Thesaurus in Dictionary Form, Revised Ed., 1978, etc., etc., etc., ...)

Can Derek farn cite even a single source for his misguided notions?? Rico402 (talk) 18:17, 23 October 2008 (UTC)

I cite Rico402, who referred to something called "Biological machines" in his tirade, as a reference that biological machines exist and should be included in the set of machines enumerated in this article. Derek farn (talk) 18:53, 23 October 2008 (UTC)

I'm certain such a citation doesn't meet Wiki guidelines. Besides, you seem to be reading content into my comments that isn't there. I never argued one way or the other whether biological machines should be included in the article, only that they are "disparate from" devices "formally defined as machines". In any case, the previous comment was primarily in regard to the use of the term "device" to describe a machine, which I argue is appropriate (within the formal definition), but which you find unsatisfactory because it would exclude biological systems.

With regard to the following-

"Is the human body as a 'machine'? (sic) In the modern - and I suppose informal - context, not only the body, but molecular mechanisms within its cells are referred to as machines. There are innumerable examples of biological machines." (Emphasis added.)

Being informally referred to as machines is not the same as being formally defined as machines. I would suggest the article differentiate between the formal classical mechanical definition (rigid or resistant bodies, useful work), the informal use of the term in describing mechanisms that don't do "useful work", and the modern (and again, informal) definition which includes electrical/electronic devices. The lines should be clearly drawn so as not to confuse the reader. Including "biological machines" may do just that, but I haven't a firm position on the matter. I do, however, take issue with airfoils and electronic components being listed as machines (even though the title says, "... and other devices"). Except for the simple machines, which are separately defined, a machine comprises a collection of parts, not a single part.

Rico402 (talk) 22:46, 23 October 2008 (UTC)

aerostats

Is a balloon a machine? It has no moving parts but generates lift by taking advantage of shifting masses of fluids of different densities under gravity to generate lift. Does that count as "using energy?"165.91.64.244 (talk) 18:05, 22 February 2009 (UTC)RKH

A balloon does not generate lift, it experiences a force because its density is lower than the surrounding medium (ie, air). Energy was expended to create the balloon, which I guess has a form of potential energy. Derek farn (talk) 22:24, 22 February 2009 (UTC)

Philosophy section

The "Philosophy" section of this article is extremely broad, almost entirely subjective, and full of POV arguments (some widely discounted). This article relates to the technology, NOT the philosophy, of machines. As such, most of this section does not belong in this article. Cheers, Rico402 (talk) 13:06, 7 November 2009 (UTC)

I would have no objection whatsoever to wholesale excision of that section. The whole thing reads like a bad freshman philosophy essay. LotLE×talk 21:11, 7 November 2009 (UTC)

Nor would I. Rico402 (talk) 22:39, 7 November 2009 (UTC)

I'm deleting this section for now, for the reasons stated above. A very much abbreviated discussion may be appropriate, but all this extraneous blather is unacceptable. Cheers, Rico402 (talk) 22:06, 10 November 2009 (UTC)

Device that transmits or modifies energy

The link to energy defines it as the capacity of a system to do work. So the definition of a machine therefore becomes a device that transmits or modifies the capacity of a system to do work. Is that right? How do you transmit a capacity to do work? I would have thought a machine would be a device that does work by modifying force.164.159.255.67 21:55, 29 January 2007 (UTC)Glen Tarr

I would think that interface components like shafts and gears "transmit a capacity to do work"; they do transmit mechanical energy after all.

Cheers, Rico402 (talk) 08:39, 5 August 2008 (UTC)

The second sentence reads "A simple machine is a device that transforms the direction or magnitude of a force without consuming any energy". I don't think this is true, and it is a vital point to make at the beginning. Force is a vector not a scalar, which means that a change in direction is acceleration and that requires energy. If a machine did not consume energy it would be the mythical perpetual motion gadget. The energy used to change direction may be small, and much has been done to minimize this energy, there is energy consumed by turning it into heat. It has been half a century since I studied physics but I haven't read where this fundamental notion has been scrapped.Roger S Johnson 20:44, 7 December 2010 (UTC) —Preceding unsigned comment added by Roger S Johnson (talk • contribs)

I removed the portion about not consuming energy, because there's no such thing as a 100% efficient machine. Wizard191 (talk) 23:06, 7 December 2010 (UTC)

What kind of things can be a machine?

Up until today this article has covered all kinds of machines. Recent edits by User:Prof_McCarthy have sought to narrow the definition to mechanical machines. I think the article should cover the general case with specific instances of machines called out in subsections or other articles. Derek farn (talk) 16:28, 27 May 2011 (UTC)

What is a machine?

This article specifically identifies a machine as a device that performs an activity. The definition of machines from its origin refers to constructions which are mechanical. There is no general notion of a machine that is specialized to a mechanical device. It is the other way around, mechanical devices or machines are used as metaphors to explain other systems. Thus, we say the human body is a machine, when clearly it is not. The reference to computers as machines, comes from the fact that originally they were actually computing machines with gears, cams, levers and more. This claim that the article was about something broader than mechanical machines, a clearly redundant phrase, is simply incorrect. The article was poorly written and misleading, I am simply trying to provide the correct information.Prof McCarthy (talk) 20:45, 27 May 2011 (UTC) — Preceding unsigned comment added by Prof McCarthy (talk • contribs) 20:42, 27 May 2011 (UTC)

The definition of a word changes over time and 100 years ago a mechanical definition would have been generally accepted. These days the term machine is used to cover a wider variety of entities. Examples obtained from following the What links here tab for the machine article include: "A computer is a machine " in Computing, "molecules that act as very tiny machines" in Colloid. In computing we even have virtual machines. Looking at your profile I see you have a mechanical background, mine is in software; we each have our own outlooks. This issue will probably only be settled by other editors giving their points of view. Derek farn (talk) 02:11, 28 May 2011 (UTC)

The use of the word machine to apply to other entities derives from its basic definition as a mechanical device constructed to accomplish a task. It is well known that the modern computer is derived from a computing machine. Microprocessor use the flow of electrons through a system of gateways to perform computations that were once done using gears, cams and linkages. There is nothing wrong with calling a computer a computing machine, but the physical properties of computers reach far beyond the usual concept of a machine, which means this is a somewhat limiting point of view. Yes, molecules, particularly structured proteins that form enzymes are being found to act like machines. This is an important insight, but again enzymes and molecules have properties that reach far beyond the concept of a machine. Yes, compilers and operating systems can be designed to be independent of the physical processor hardware and are therefore said to be machine independent. Yes, the software that provides this independence is called a virtual machine. However, this again uses the concept of a machine as a metaphor to represent physical operations. This is not a defining characteristic of the computer, compiler, operating system or virtual machine. It is simply evocative language. Please let a machine be what we know it is, a mechanical device constructed by someone to accomplish a task.Prof McCarthy (talk) 05:56, 28 May 2011 (UTC)68.101.120.164 (talk) 05:53, 28 May 2011 (UTC)

Putting aside, for the time being, whether the uses I gave above are metaphors or not; what is a mechanical device? Mechanics says "the branch of physics concerned with the behavior of physical bodies" and physical body "a collection of masses, taken to be one". I take it we all agree that an internal combustion engine is a machine, what about a Molecular motor? Both are made up of physical bodies, although these bodies differ in size. What about entities built using Nanotechnology, they are commonly referred to as machines. While a computer is built using physical bodies its moving parts are electrons and photons. Prof McCarthy, is it the use of electrons and photons rather than collections of atoms that prevent you regarding a computer as a machine? Derek farn (talk) 15:11, 28 May 2011 (UTC)

What is at issue here is the characterization of a machine not all of the ways that that characterization can be applied to other things. Clearly the color red is something that makes sense, so we do not have to characterize red by listing all of the things that can be painted red. I am not trying to prevent anyone from regarding any thing as a machine. I am simply trying to accurately characterize what a machine is so that it is clear what it means to say a thing is a machine. Prof McCarthy (talk) 15:26, 28 May 2011 (UTC)

Yes, we are trying to enumerate the characteristics an entity has to have for it to be regarded as a machine, not as a metaphor for a machine. In my line of work the term "machine" is shorthand for computing machine (I am not using it in a metaphorical sense) and if I want to refer to a mechanical machine I would say "mechanical machine"; in your (Prof McCarthy) line of work I imagine you apply the opposite usage. The machine article needs to be broad enough to cover all common uses and should not give preference to one application domain. Derek farn (talk) 16:53, 28 May 2011 (UTC)

As you must know that there is no question that a computing machine was assembled from gears, cams and linkages and fits exactly the characterization of a machine I am trying to present. The fact that a computer is no longer constructed in that way does not change the meaning of the word machine. It is possible to abstract the notion of a machine to a system with inputs and outputs, and if you feel qualified I would recommend that you write that article. But please leave the basics of a machine to what we know them to be. Prof McCarthy (talk) 17:02, 28 May 2011 (UTC)

I am confused. Are you saying that modern computers are machines only because in the past they were constructed from moving gears, cams and linkages? What essential characteristic is missing from a computer whose only moving parts are electrons and photons that prevents it being included in the list of entities that are machines? I can atest to the fact that there is a group of people who call such entities 'machines'. At the moment this discussion involves two people with opposing views and unless more editors join in the call for a change to the status quo the introduction remains as it has been for some time. Derek farn (talk) 17:21, 28 May 2011 (UTC)

The language of computer science draws heavily from the language of machines, and given the history of the design of computing machines this is clearly appropriate. The concepts of state machines, turing machines, virtual machines, and even the term "machine room" for the location of a computer all hark back to the original computing machines. However, these various uses of the term machine are actually based on an abstraction of a machine to a construction that transforms a specific input into s specific output. It is my opinion that before we can present and justify this abstraction and its application to computer science, we must first clearly explain what machines are. Prof McCarthy (talk) 18:28, 28 May 2011 (UTC)

The new version of this article looks much better. I have told my students to stay away from Wikipedia on this topic, but I like this new direction. — Preceding unsigned comment added by 169.234.11.254 (talk) 23:13, 28 May 2011 (UTC)

Narrow Focus

The judgement that the introduction is narrowly focussed is incorrect. A clear definition of a machine as the mechanical device that it is, makes more clear its usage in other areas. It is not limiting, it broadens understanding. The current discussion of moving part and redirected forces is misleading and wrong. It must be changed because it does not describe machines as we know them or the many other usages of the term machine that concern our computer science colleague. Prof McCarthy (talk) 17:01, 29 May 2011 (UTC)

I moved the offending discussion of machine elements to its own heading, and added a sentence describing other uses of the term machine. This has got to be enough to stop our colleagues edit warring. Prof McCarthy (talk) 17:30, 29 May 2011 (UTC)

Energy and Work

Activity is movement. Energy and Work must be transferred over time to perform an activity. This means the primary feature of a machine is its ability to process power. This is true even for computers that manipulate the flow of electrons. Power is the primary concept, not energy and work. This is why I have stated repeatedly in the discussion "what is a machine" that the current introduction is wrong and misleading. Yet our colleague Derek farn keeps reverting my changes back to the original. Prof McCarthy (talk) 16:05, 30 May 2011 (UTC)

Move and Store Electrons?

If Derek farn's concept of a computer is a machine that moves and stores electrons, then there is not much more that I can say. Most every one of my computer science colleagues focus on the processing of information. I suspect this means he is more focussed on the computer engineering aspects of computers. This would seem to be the essence of a narrow focus, and perhaps he should not ascribe this name to others. Prof McCarthy (talk) 16:05, 30 May 2011 (UTC)

In order to characterize a computer as a machine that moves and stores electrons, Derek farn eliminated the discussion of Babbage's Difference Engine and Analytical Engine. Babbage's Difference engine was the first mechanical calculator, and his Analytical engine introduced flow control and memory that qualified it to be the first computer. This is an example of a personal perspective that is limiting the potential for this article. Prof McCarthy (talk) 16:15, 30 May 2011 (UTC)

Transistor switches, wow!

Derek farn is so concerned that a computer be defined as a machine that he includes "transistor switches" as an element that controls movement. If this is what is necessary to keep him happy, then so be it. I have to say, I believe most people would consider a computer to be somewhat more than this definition of a machine. The ability to directly process information is something that machines do not do very well. In fact, it is routine for modern machines to include a computer to provide this information processing capability. Prof McCarthy (talk) 22:35, 30 May 2011 (UTC)

What is wrong with Franz Reuleaux?

Our colleague Derek farn does not want quotations from perhaps the most famous of the machine theorists Franz Reuleaux, or from recent texts on machine theory. I suppose this is because these quotes emphasize the role of power in machines, which bothers him for some reason. When are we going to be allowed to make this the article it should be? Prof McCarthy (talk) 02:46, 31 May 2011 (UTC)

Babbage's Analytical Engine

Our colleague Derek farn strikes again. It is the Analytical Engine developed by Charles Babbage which is considered to have all the features of a computer, including flow control and memory. However, he has wiped out this sentence from the discussion of computing machines, and left two incorrect statements (1) that Babbage's difference engine was the first computer, and (2) that it was never constructed. Prof McCarthy (talk) 02:53, 31 May 2011 (UTC)

Linkage section deleted

Derek farn deleted the section on linkages which is reproduced below, because he claims it duplicates the Wikipedia article on Linkages, even though it provides only the briefest summary in the context of this article on Machines, and provides useful links to examples that are not readily available in the Linkage article. Out of respect for the wikipedia traditions, I am leaving his edits unchanged, but I must say that they do not make sense. Then again, this is the guy who says a computer is a machine that pushes electrons around. Prof McCarthy (talk) 02:04, 1 June 2011 (UTC)

Linkages

A linkage is a collection of links connected by joints. Generally, the links are the structural elements and the joints allow movement. Perhaps the single most useful example is the planar four-bar linkage. However, there are many more special linkages:

• Watt's linkage is a four-bar linkage that generates an approximate straight line. It was critical to the operation of his design for the steam engine. This linkage also appears in vehicle suspensions to prevent side-to-side movement of the body relative to the wheels. Also see the article Parallel motion.
• The success of Watt's linkage lead to the design of similar approximate straight-line linkages, such as Hoeken's linkage and Chebyshev's linkage.
• The Peaucellier linkage generates a true straight-line output from a rotary input.
• The Sarrus linkage is a spatial linkage that generates straight-line movement from a rotary input.
• The Klann linkage and the Jansen linkage are recent inventions. They are six-bar linkages that provides interesting walking movements.

Mechanical machine

Articles on Molecular machine and Computing machines exist and perhaps other articles with machine in the title (I have not looked). An article with the title Mechanical machine does not currently exist and is a large area that needs to be covered at some point. Derek farn (talk) 21:26, 1 June 2011 (UTC)

Derek farn, Thank you for this suggestion. I know that you do not agree, but I believe most would consider "mechanical machine" to be redundant, in the same way as the phrase "computing computer." I recognize your desire to have a computer be a machine that does not have moving parts but causes the movement and storage of electrons in a way that allows the processing of information. I wish that you could be persuaded that computers are much more than the computing machines that are their ancestors. The distinction is easy, if you will allow it. The primary feature of a machine is the management of power, and if you insist you can view a computer as managing power as well. The real contrast between a machine and a computer arises when you consider their ability to manage information. It is possible to create mechanical programs and mechanical memory, but most would agree that it is an awkward and flawed process, and therefore they would accept that computers are much more than machines. This becomes particularly clear when you recognize that modern mechanical systems include computers, specifically to manage information in controllers and user interfaces. I doubt that I can convince you, but I tried. Prof McCarthy (talk) 00:56, 2 June 2011 (UTC)

Prof McCarthy, the phrase "management of power" is very seductive but is it overly broad in some cases (eg, if I mix two substances and there is a chemical reaction, is it a machine? Using a compression cycle/heat exchanger to liquify air is management of power, is it a machine?) and overly narrow in others (eg, the idea of a biological cell as being a machine that produces/consumes proteins etc)? Would "most" people consider the term "mechanical machine" redundant? I think it depends on the application domain, within computing it would not be considered redundant, I don't know about molecular biology and I guess it would be considered such in your own field. Without wishing to get too philosophical, computers do not "manage information", this is an abstract idea that people use when thinking about computers (they may be more than machines, but the same could be said of automobiles). Computers are involved in reading/writing electron charge/magnetic fields/photons and moving these around; computers manipulate lots of power which is why they get so hot. There is a lot more to information than first meets the eye; recently physicists have proposed the Holographic principle which describes the universe in terms of its information content. Derek farn (talk) 02:28, 2 June 2011 (UTC)

Derek farn, Thank you for sharing these ideas. The use of the phrase "management of power" is not to replace the definition of a machine but to provide a concise way of explaining what it does. Machines use energy over time, which is power. Machines apply forces and cause movement which combine to define power. If you really want to, you can apply this to everything in the world, but this does not mean everything should be viewed as a machine. A machine is a human construct, a tool, not a living biological system. Computers manage information, and depending on your point of view you can say all things manage information in some way, but this does not mean all things are computers. If we can stay focussed for the moment on machines and computers, I believe we can allow machines to be as I have tried to describe them, and allow computers to be machines that have information processing capabilities. If you do not like this then so be it. Prof McCarthy (talk) 06:15, 2 June 2011 (UTC)

Prof McCarthy, I was think that the phrase "management of power" might be used to argment the definition, see below. The reason for asking the questions about what you consider to be a machine is to help me understand your point of view. I think I now understand your conception of a computer (please correct me if I am wrong) in terms of its intended use, i.e., the reason for building it is to process information not to move electrons around; following through with this line of reasoning (again, please correct me if I have misunderstood) an internal combustion engine is not a machine because the reason for building it is to transport people not to have pistons go up and down and cams go round.

What do you think of the following possible changes to the first line "A machine is a device that uses energy to perform some activity, i.e., it manages power" or "A machine is a device that manages power, i.e., it uses energy to perform some activity", or something else?

Derek farn, I am not sure how you arrive at the conclusion that I am trying to define a machine or computer in terms of its intended use. My focus on power for a machine is to provide an organizing principle that helps a reader understand a wide range of information about machines. My discussion of information processing for a computer is to provide a distinction between computers and machines. I am simply trying to write a clear, correct and useful article about machines. Someone else can write about the philosophical principles that underlie the definitions of things. Prof McCarthy (talk) 12:42, 2 June 2011 (UTC)

Prof McCarthy, I am trying to understand what characteristic you think machines have that computers do not; ok, I jumped to the wrong conclusion with "intended use". Can you flesh out this idea of "management of power" (I think it is an attractive one for a general definition of machine) to show how it excludes computers (many of which include a lot of electrical power management). Derek farn (talk) 15:50, 2 June 2011 (UTC)

Derek farn, As I have said many times, the issue is not what machines have that computers do not have, but the other way around. It does not make sense to focus on the way a computer manages electric power, when its remarkable capabilities center on information processing. Similarly, it make more sense to study machines based on the the way they manage power, not how they process information. However, I get it you want machines and computers to be characterized in exactly the same way throughout the entire article, why I cannot imagine. Prof McCarthy (talk) 22:24, 2 June 2011 (UTC)

Prof McCarthy, I don't understand your fixation that because computers process information they are not machines. I guess we will have to agree to disagree. On another note there is an article called outline of machines that cover the same ground as machine (I don't understand the meaning of the article title), perhaps we should suggest that the two articles be merged? Again I would suggest that you create an article covering Mechanical machines. Derek farn (talk) 00:53, 3 June 2011 (UTC)

Derek farm, Again, I have not said that computers are not machines. Please read this discussion from the beginning and you will see that what I am saying is that computers are more than machines, and that a clear presentation of the principles of machines misses the point when it comes to computers. And in reverse, trying to fit a description of computers into an article on machines forces misleading and inaccurate statements. I do not understand your fixation with limiting the description of a computer to that of a machine. Please consider presenting your perspective in an article on computing machines, and let me provide a clear, correct and useful article on machines. Prof McCarthy (talk) 03:57, 3 June 2011 (UTC)

Prof McCarthy, is your reasoning that because computers are so much more than machines the article on machines should be written in a way that excludes computers from the set of devices considered to be a machine (i.e., a machine is a "mechanical system")? Derek farn (talk) 19:45, 5 June 2011 (UTC)

Derek farn, The term "mechanical system" has been used for over 50 years to refer to a broad class of machines including servo-controlled machines. In recent decades mechanical system has been interpreted to include a computer controller. Please relax, you must know that your sensitivity to the relationship of computers and machines is always in the forefront of my concerns when writing in this article. I will be very careful with your feelings on this matter. All I ask is that you do not demand that this article apply to a stand-alone computer. This is the distinction that I have asked for from the beginning. Prof McCarthy (talk) 05:06, 6 June 2011 (UTC)

Prof McCarthy, why don't you try to refute my examples with reasoning rather than making trite comments like the one above? How do you reconcile the use of the term "mechanical system" with transistor being listed as a component of a machine? What characteristics does a stand-alone computer not have that means excludes it from the set of devices considered to be a machine? Derek farn (talk) 09:47, 6 June 2011 (UTC)

OK Derek, I will write the article with computers as machines

I thought I have been clear about why an article on machines did not need to describe a computer as a machine. How many times can I make the argument that computers are described very clearly in wikipedia as devices that process information, and to force an article on machines to also address computers is not just awkward but leads to incorrect and misleading statements. None the less, Derek demands that this is the way we must proceed. So, I will do this, beginning with the definition that a "Machine is a mechanical system or a computer or a combination of the two. If it is a mechanical system then it is designed to manage power to accomplish a task, and if it is a computer then it is designed to manage power to process information." I believe that I can do this in a way that makes Derek happy and at least gets some correct information into the article.Prof McCarthy (talk) 03:47, 7 June 2011 (UTC)

Sorry a mechanical system already includes a computer, which means the definition we will use is "A machine is a mechanical system or a computer." Good enough.Prof McCarthy (talk) 04:09, 7 June 2011 (UTC)

Prof McCarthy, why do you continue to insist that the phrase "mechanical system" be used? The only answer I can come up with is that you are so focused on your own area of expertise that you fail to see the wider meaning. What about molecular machines, shouldn't they also be listed along with computers and "mechanical systems"? The introduction would quickly become unwieldy if every kind of machine was listed. Derek farn (talk) 11:06, 7 June 2011 (UTC)

I get it, nothing that I have explained above has made any sense to you. You cannot understand "mechanical system" as a general concept that covers all of the machine. Fine, then lets address directly the machines that you want discussed in this article: mechanical systems, computers, molecular machines, biological machines. Let me know if there are any more.Prof McCarthy (talk) —Preceding undated comment added 12:01, 7 June 2011 (UTC).

Prof McCarthy, after lots of to-and-fro we have finally come up with wording that generally improves the article. Is a molecular machine a subset of biological machine, I await somebody with more expertise than me in this area to make this call. Derek farn (talk) 12:30, 7 June 2011 (UTC)

If you consider this progress, then fine. I will work with it. Prof McCarthy (talk) 13:10, 7 June 2011 (UTC)

All right, a radio and a television are machines too

In order to make progress, anything Derek farn wants to be a machine is a machine. We will get this done. Prof McCarthy (talk) 13:36, 7 June 2011 (UTC)

Prof McCarthy, please improve your behavior on this talk page, this Derek farn is trying to be constructive while your responses aren't. The definition of a machine is far more than just a mechanical device. Electronics easily fall within the definition of a machine. For a reference, see the dictionary: http://www.thefreedictionary.com/machine. Wizard191 (talk) 18:19, 7 June 2011 (UTC)

Wizard 191, Thank you for this contribution. Please note that electronic systems and computing systems are well represented in Wikipedia by a number of articles. In contrast, the keyword mechanical systems links directly to this article on machines. As I have said repeatedly to our colleague Derek farn the issue is not whether something is to be called a machine, instead it is what is needed in this article on machines. The demand that every topic apply to electronic and computers systems simply does not make sense, because it does not allow a clear presentation of the principles of the systems we know as machines. But as I have said, I will soldier on and allow you and Derek to add all the corrections you feel are necessary to include electronica systems, computers and whatever else you want to include as machines. Prof McCarthy (talk) 19:30, 7 June 2011 (UTC)

While I don't disagree with the fact that the mechanical aspects were quite lacking (now they are much better because of your contributions), that doesn't mean that all other aspects of a machine be ignored. Derek farn's recommendation to make a new article called mechanical machine is a good one seeing how it's a compromise between your POV and ours. Wizard191 (talk) 19:47, 7 June 2011 (UTC)

Sorry, I cannot agree that "mechanical machine" is a sensible topic for an article, it is equivalent to "computing computer," or "electrical electronics." If you want to separate Derek farn and me, then separate the link between mechanical system and machine. I will gladly move all of my writing to an article on mechanical systems, and let this article on machines languish as a catchall for whatever devices you and he want it to be. Prof McCarthy (talk) 20:04, 7 June 2011 (UTC)

Your argument is quite flawed. All computers compute by definition (and a computer is still a machine); all electronics use electricity by definition (and electronics are still machines); however all machines do not "machine", or another way you might argue is, all machines do not "mechanize". As such, either accept the compromise or move on to another part Wikipedia that is a less contentious topic for you. Wizard191 (talk) 21:49, 7 June 2011 (UTC)

My argument is flawed because you and Derek farn want a computer and a television and a biological organism to be defined as a machine in an article that is linked to the words "mechanical system?" I am afraid it is hard to make your position make sense. Please accept my compromise which is to separate the link from "mechanical system" to "machines". I will happily move to the article on mechanical systems and let you and Derek farn propagate your views on machines in this article. Prof McCarthy (talk) 23:18, 7 June 2011 (UTC)

If you do not mind, I will move to mechanical systems.

Colleagues, Thank you for your time. I will copy my contents from this page to the page on mechanical systems. You can revert the page back to before my contributions. Best regards, Prof McCarthy (talk) 23:54, 7 June 2011 (UTC)

Please create an article "Machine (mechanical)"

{{adminhelp}} I have been persuaded that it is impossible to address the sensitivity to the usage of the word machine, without explicitly introducing an article on machines that are mechanical in order to distinguish them from machines that are not mechanical. Please create this page so that I can use it to coordinate topics that address the mechanical aspects of machines. Thank you Prof McCarthy (talk) 14:00, 12 June 2011 (UTC)

Looks like you succeeded without admin assistance: Machine (mechanical). Favonian (talk) 15:18, 12 June 2011 (UTC)

Machine design?

The major phases of machine design now include (iv) rebel? This article is evolving in an interesting direction. While I am at it, a device that "transforms the direction or magnitude of a force" seems to be a flawed definition of a simple machine. Two pillars that support a roof transform the weight of the roof into two separate forces acting on the ground, but I do not think anyone would consider pillars to form a simple machine. Prof McCarthy (talk) 05:48, 26 September 2011 (UTC)

I am glad to see that "rebel" is no longer a phase of machine design. However, the definition of simple machines still seems to be flawed. Prof McCarthy (talk) 06:39, 3 October 2011 (UTC)

Machine means Computer

It seems this page is moving toward defining a machine as a computer. I suppose this was an inevitable result of the discussions above. In my opinion, this misrepresents both machine and computer and is a disservice to the community that uses Wikipedia. Prof McCarthy (talk) 06:31, 9 October 2011 (UTC)

Where is Derek farn, when you need him? I do not think he would have allowed the new section "types of computers" to draw so heavily on the article Classes of computers. Prof McCarthy (talk) 09:43, 23 October 2011 (UTC)

Indeed. That addition is more like a badly written highschool essay and does not improve this article. --VanBurenen (talk) 11:12, 23 October 2011 (UTC)

I missed that rather excessive addition, pleased to see that others were paying more attention. Sometimes a section of an article does grow into something that could be an article in its own right, but this is not the case here.Derek farn (talk) 13:54, 23 October 2011 (UTC)

The thing is, that computers can built from mechanical parts, so it is undeniably true that at least some computers are machines. Or what about fluidic logic? Those are clearly machines as well. And you can make machines that consist partially of electronics or fluidic logic. It's probably illogical to consider these parts as not part of the machine, but not necessarily wrong; it depends on your definition of machine. But I think if you include them, the definition of machine becomes more general and more useful. I think the article should take a systems view, which would include electronics and electromechanical, and even chemical parts.GliderMaven (talk) 14:46, 27 March 2012 (UTC)

I'm changing my mind on this. If we define 'machine' too broadly for the purposes of deciding what the article covers then it just becomes a tool. But I don't think that all tools are machines, although the only counterexample I've managed to come up with so far is a computer/electronics, but that only works if we define a machine in terms of simple machines.GliderMaven (talk) 22:12, 31 March 2012 (UTC)

MMMm. Dunno yet. The other thing is that the while the German wikipedia has an article on computing machines the Wikipedia has a weird article abstract machine; which seems pretty badly written.GliderMaven (talk) 22:12, 31 March 2012 (UTC)

Definition of machine

I found the reference to the American Heritage definition of machines in the first sentence of this article to be helpful. Here is that definition:

1. a. A device consisting of fixed and moving parts that modifies mechanical energy and transmits it in a more useful form. b. See simple machine. c. See compound machine.

2. A system or device for doing work, as an automobile or jackhammer, together with its power source and auxiliary equipment.

3. A system or device, such as a computer, that performs or assists in the performance of a human task:The machine is down.

4. An intricate natural system or organism, such as the human body.

5. A person who acts in a rigid, mechanical, or unconscious manner.

6. An organized group of people whose members are or appear to be under the control of one or more leaders:a political machine.

7. a. A device used to produce a stage effect, especially a mechanical means of lowering an actor onto the stage. b. A literary device used to produce an effect, especially the introduction of a supernatural being to resolve a plot.

8. An answering machine:Leave a message on my machine if I'm not home.

adj. Of, relating to, or felt to resemble a machine:machine repairs; machine politics.

v.ma·chined, ma·chin·ing, ma·chines v.tr. To cut, shape, or finish by machine. v.intr. To be cut, shaped, or finished by machine:This metal machines easily.

Prof McCarthy (talk) 16:53, 1 April 2012 (UTC)

Definition of computer

The American Heritage dictionary also provides a useful definition of a computer:

1. a. A device that computes, especially a programmable electronic machine that performs high-speed mathematical or logical operations or that assembles, stores, correlates, or otherwise processes information. b. Such a device along with peripherals, especially a monitor, keyboard, and mouse.

2. One who computes.

Prof McCarthy (talk) 16:53, 1 April 2012 (UTC)

Robert Willis 1841

I believe this edit by Phmoreno was reverted because the block quote was mistakenly attributed to Karl Marx. The reference is actually from a book by Robert Willis, perhaps the first textbook on mechanisms. The sentence after the block quote refers to a different reference that provides an interesting perspective on machines by Karl Marx.

In an early engineering text a machine is defined as follows:

“Every machine is constructed for the purpose of performing certain mechanical operations, each of which supposes the existence of two other things besides the machine in question, namely, a moving power, and an object subject to the operation, which may be termed the work to be done. Machines, in fact, are interposed between the power and the work, for the purpose of adapting the one to the other.”

A discussion of the definition of a machine is given by Karl Marx in Chapter 15 of Capital.

References

Prof McCarthy (talk) 03:46, 22 April 2012 (UTC)

Mechanization

The Merriam-Webster dictionary defines "mechanize" as a transitive verb which is "to make mechanical," especially to make automatic or routine. One would think this is consistent with the meaning of "machine." However, Phmoreno has had this revision reverted for no clear reason. Prof McCarthy (talk) 19:55, 7 May 2012 (UTC)

Powered Tools ???? Inclined plane, Wheel and axle, Lever, Pulley, Wedge, Screw"

The article defines machines as powered tools, then lists simple machines -- all of which are not powered! I just removed the vague "device" in the 1st paragraph, simplifying but not changing the definition of machine. But fixing the powered/simple problem is more than I want to undertake.76.103.213.6 (talk) 01:44, 5 September 2012 (UTC)

I agree. The cited source does not imply that all machines are powered, but the article does. I think removal of "powered tool" from the definition should be enough fix it. I'll do that for now. Burninthruthesky (talk) 16:28, 21 December 2012 (UTC)

What does it mean to be "powered"? My mother's sewing machine was hand-operated. Does that make it powered by hand? If I throw a rock at somebody's head, that is powered by hand but it doesn't make it a war machine.

Meanwhile I am getting increasingly unhappy about the idea that something as simple as a hand axe is a "machine". First of all, there is a distinction between an "machine" and a "mechanism": a mechanism comprises one or more moving parts and will often form part of a larger machine. For example a sewing machine includes amongst other things a mechanism for feeding the thread out. A hand axe is simpler still and while it is certainly a tool, and a lever is a mechanism, I know of no reference for describing such things as "machines". This article needs to either reference such a definition or get rid of any incorrect usage. — Cheers, Steelpillow (Talk) 18:24, 21 December 2012 (UTC)

You're right, the "power" in the physics sense can include any input of energy, including human input. The definition in the cited dictionary which is now online links to a further definition of "simple machine", which includes "wedge". The article comments on the wedge-like mechanism of an axe. I hope this answers your concerns. Burninthruthesky (talk) 19:29, 21 December 2012 (UTC)

OK, thanks for the clarification. — Cheers, Steelpillow (Talk) 21:53, 21 December 2012 (UTC)