Underdetermination

Ancient Greek skeptics argued for equipollence, the view that reasons for and against claims are equally balanced.

As a result, any conclusion about such a reference frame was underdetermined; it was equally consistent with the theory to say that the solar system is at rest, as it is to say that it moves at any constant velocity in any particular direction.

Goethe showed that this step from observation to theory is more problematic than Newton wanted to admit.

And Goethe's insight is surprisingly significant, because he correctly claimed that all of the results of Newton's prism experiments fit a theoretical alternative equally well.

If this is correct, then by suggesting an alternative to a well-established physical theory, Goethe developed the problem of underdetermination a century before Duhem and Quine's famous argument."

(Mueller, 2016)[3] Hermann von Helmholtz says of this, "And I for one do not know how anyone, regardless of what his views about colours are, can deny that the theory in itself is fully consequent, that its assumptions, once granted, explain the facts treated completely and indeed simply".

[4] Experimental violations of Bell inequality show, that there are some limitations to underdetermination – every theory exhibiting local realism and statistical independence was disproved by this tests.

Some skeptical arguments appeal to the fact that no possible evidence could be incompatible with 'skeptical hypotheses' like the maintenance of a complex illusion by Descartes' evil demon or (in a modern version) the machines who run the Matrix.

Underdetermined ideas are not implied to be incorrect (taking into account present evidence); rather, we cannot know if they are correct.

A more general response from the scientific realist is to argue that underdetermination is no special problem for science, because, as indicated earlier in this article, all knowledge that is directly or indirectly supported by evidence suffers from it—for example, conjectures concerning unobserved observables.

It is therefore too powerful an argument to have any significance in the philosophy of science, since it does not cast doubt uniquely on conjectured unobservables.