Today I was watching Professor Walter Lewin's lecture on Newton's laws of motion. While defining Newton's first, second and third law he asked "Can Newton's laws of motion be proved?" and according to him the answer was NO!
He said that these laws are in agreement with nature and experiments follow these laws whenever done. You will find that these laws are always obeyed (to an extent). You can certainly say that a ball moving with constant velocity on a frictionless surface will never stop unless you apply some force on it, yet you cannot prove it.
My question is that if Newton's laws of motion can't be proved then what about those proofs which we do in high school (see this, this)?
I tried to get the answer from previously asked question on this site but unfortunately none of the answers are what I am hoping to get. Finally, the question I'm asking is: Can Newton's laws of motion be proved?
Best Answer
If you want to prove something, you have to start with axioms that are presumed to be true. What would you choose to be the axioms in this case?
Newton's Laws are in effect the axioms, chosen (as others have pointed out) because their predictions agree with experience. It's undoubtedly possible to prove Newton's Laws starting from a different set of axioms, but that just kicks the can down the road.