When Dalton gave his atomic theory, he postulated that atoms were the smallest indivisible part of matter. But now we know that they are composed of even smaller particles. So, the postulate has been proven wrong. Similarly, can other postulates like the postulates of Special Relativity be proven wrong?

  • 1
    $\begingroup$ In science, we test theories' predictions against data, then realize something has to be rejected if they're wrong (although which postulate revisions are most helpful takes some trial & error). So far, relativity is doing well. $\endgroup$
    – J.G.
    Dec 6, 2021 at 11:01

1 Answer 1


Yes, in principle postulates can be found to be wrong, or more usually unnecessary.

That could lead to an abandonment of the theory, or extensions, as in this example.

It's about the postulates of geometry, from Euclid, the parallel postulate

The postulate was long considered to be obvious or inevitable, but proofs were elusive. Eventually it was discovered that inverting the postulate gave valid, albeit different geometries. A geometry where the parallel postulate does not hold is known as a non-Euclidean geometry.

  • 1
    $\begingroup$ maybe one should add "wrong if it is found they lead to wrong experimental predictions" $\endgroup$
    – anna v
    Dec 6, 2021 at 9:17
  • 1
    $\begingroup$ @anna v, yes that's true. $\endgroup$ Dec 6, 2021 at 9:26

Not the answer you're looking for? Browse other questions tagged or ask your own question.