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A mechanical engineer told me Science isn't useful?

  1. Mar 22, 2010 #1
    I talked to a mechanical engineer the other day, and he said "Science and physics isn't all that useful." :confused::confused:

    I'm curious what a good response to that would be?

    He said when he works on his projects, the "big picture" is the project, and Science and other aspects are only small details or parts to the whole. He said physics ignores very important details when he works on his projects, such as "friction", etc. He said if you get lost in the details like physics you'll miss the forest from the trees. He said, "We'll leave theories and hypotheses to the physicists. I'm a no nonsense type of guy who likes to be practical. If something's not useful and is 'theories', I don't care."

    Any ideas for comebacks?
  2. jcsd
  3. Mar 22, 2010 #2
    There's your problem!

    *runs and hides*
  4. Mar 22, 2010 #3


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    If a machine isn't working does he look for evidence of damage to a part? Does he try running the machine after removing/replacing certain parts?
    or does he just roll dice to work out what's wrong?
    That's science.

    On the other hand, in most of fluid dynamics, aerodynamics and some parts of stress calculation I would rather have a large engineering safety margin than a 'theory' which assumes a spherical horse running in vacuum!
  5. Mar 22, 2010 #4


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    I'm sorry, but I have a hard time believing anyone with an engineering degree would make a statement like that. Perhaps he was joking? If he wasn't, I'm going to go ahead and say that he was talking out of his rectum.
  6. Mar 22, 2010 #5


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    If he said physics textbooks/lectures/students ignore details like friction he would be perfectly correct (at least at an undergrad level)

    How many questions about projectiles do you get here that ignore air resistance?
  7. Mar 22, 2010 #6


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    So calculating fluid, sliding, and rolling friction are exclusive to engineering problems? Does one not learn about friction in classical mechanics?

    Edit: I think I'm just having problems with the choice of words. To me, given that engineering is just a sub-discipline of physics, his statement sounds similar to an actuary claiming that mathematics ignores probability theorems.
    Last edited: Mar 22, 2010
  8. Mar 22, 2010 #7
    Sounds to me like your friend is rather ignorant! It happens that people get preconceived ideas about certain subjects (though in this case, somehow, all of science..) and they just blanket believe it from then on: seems as though this is the situation your friend finds himself in, a remnant from a high school physics course he perhaps didn't enjoy.

    Next time your friend tries to use GPS (I choose this for the sake of practicality, I think you could probably replace it with any object you can possibly think of), kindly remind him that, as a non-believer in science, he isn't allowed. General relativity doesn't like him either. :smile:
  9. Mar 22, 2010 #8


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    My, my. Is it possible that the OP has spoken to an ME with a talent for "human engineering" and has wrangled a job that requires no actual skill? I worked with such an ME about 25 years ago. He is an Indian engineer with tons of Dale Carnegie courses under his belt, and he treated people under him with absolute disdain. I can't think of any people (OK, maybe one) in that company that were more hated. He showed nothing but rudeness and dismissal to people that were doing their best to advance the goals of the company. If he ever gets to upper-level management in any company, I will buy derivatives betting against it in a heartbeat.

    BTW: I apologize for going postal over a jerk so far back that many of you had not been alive then. At least you missed the experience. BONUS!!!!!!!!!
    Last edited: Mar 22, 2010
  10. Mar 22, 2010 #9
    Sure: "You're a clown."

    Enough said.
  11. Mar 22, 2010 #10
    I know an experienced electrical engineer that doesn't believe in quantum mechanics. After days of discussions and explanations, I gave up. I probably pissed him off too.
  12. Mar 22, 2010 #11

    He didn't take a course in solid state physics? We were shown from the ground up with energy band diagrams and such.
  13. Mar 22, 2010 #12
    Hmm, this whole scientia sibi / scientia homini is a bit awkward to me.

    What is practical use? makes life easier? why do we want life to be easier? to do more stuff we want to do, why? because we like to do those things.

    Why do we practice pure science? because we like the search for knowledge as a hobby.

    It's the same thing, the former is just for a person who has one hobby less than pure scientists, a pursuit of knowledge, the thrill of solving complex puzzles, if you like.
  14. Mar 23, 2010 #13
    tell him that if it wasn't for theories and hypotheses, even the steam engine wouldn't be possible. engineering is only the practical application of whatever science teaches us.
  15. Mar 23, 2010 #14


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    1) You always run into a few who survived their college classes as opposed to actually learning the material. A lot of those just hope to wind up in a job that's not too challenging.

    2) Quite a few of those still perform well on a job they've held for several years because experience is its own kind of knowledge. Quite a few nicely laid out designs just don't work because of variation in parts, etc. If you've seen enough similar problems, experience can be a good guide for determining which parts of the design most likely have to be tweaked. (That person is still going to have a hard time if he moves on into a new job.)

    Even in classes, I've had a few circuits where the ideal values just don't work (mainly because your real parts don't have ideal values). The two options seemed to be to hopefully figure out which part(s) were the main cause of the problem, swapping new parts in and seeing what happened, and estimating what value for the key parts would give you the desired output - or grabbing several parts of the desired values and selecting only parts that are very close to the ideal values (that could get a little tedious with a lot of parts).
  16. Mar 23, 2010 #15
    Yeah, well, after the science is done, you need the engineers to engineer and write emails, then reengineer and write more stuff and rereengineer write alot more emails, and someday they might get it right, but don't take it to the bank. 90% of them don't really engineer anyway, and you try to converse with them in the field in which they are titled it shows.
    Last edited: Mar 23, 2010
  17. Mar 23, 2010 #16
    I think you have the cart before the horse. Modern Thermodynamics started with the study of how steam engines work (Carnot:Reflections on the Motive Power of Fire). Newcomen and Watt didn't use theory to design their machines.

    For that matter, Engineers were building buildings and bridges for thousands of years before Statics was developed. The Parthenon and Chartres were built using nothing but rule of thumb.

    I don't suppose that Electronics and Electrical Engineering could have gotten very far without the theoretical work of Maxwell et al, but even in this area, Edison didn't seem to have much use for theory. Even when you have a useful theory, a huge amount of trial and error goes into learning how to apply the theory. Remember the saying, "In theory, theory and practice are the same. In practice, they are not."

    I suggest reading the book by L. Sprague De Camp, "The Ancient Engineers".
  18. Mar 23, 2010 #17
    The Parthenon?

    I thought the entire acropolis was supposed to be a work of mathematical perfection.
  19. Mar 23, 2010 #18
    But which came first? The philosophers mathematical perfection? or the rules of thumb that worked so well?
  20. Mar 23, 2010 #19


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    It's one of the great stories of British engineering.
    Britain's railways in the first half of the 19C, were built by illiterate northerners who didn't trust figures so just massively over-engineered everything. It's called a margin of ignorance - like a margin of safety.

    The French however had the best engineering schools and the most brilliant mathematicians and they built bridges that were perfectly designed.
    Unfortunately they didn't understand about things like stress concentrations that meant a material is only a few % as strong in real life as it is in the textbook.

    The result (according to British engineers) is that lines built by Stephenson and Locke are still being used today, while everything built in Europe before Eiffel fell down.

    It's not really true - but makes a good story.
  21. Mar 23, 2010 #20
    The math was for esthetic purposes, not engineering. The Greeks had all sorts of ideas about what ratios and proportions were esthetically pleasing. The Pythagorean mystery cult also built all sorts for numbers into buildings they were constructing. You can see a lot of this numerlogy carried forward in Plato.

    When I was taking number Ancient Architecture, when my professor was talking about the Pythagoreons in relation to a temple in Sicily. I pointed out that the temple had 6 columns on the short side and 13 on the long side which meant the spaces between the columns were 5 and 12. 52+122=132 which is called a Pythagorean triple. Oddly enough, no one had noticed that before.

    http://en.wikipedia.org/wiki/Pythagorean_triple" [Broken]

    My professor ended up writing a paper about architecture and the Pythagoreons and I got a nice footnote in it.
    Last edited by a moderator: May 4, 2017
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