What are the unprovable assumptions that are required in order for scientific, empirical investigation to be considered both valid and worthwhile?
For example - I would suggest that the existence of an objective reality that is external and common to all is an unprovable but necessary assumption for scientific investigation to be considered valid and worthwhile.
That is to say that you are not a brain in a jar (or any other similar scenario) subjectively constructing all that you perceive. Instead we are each individual consciousnesses subjectively experiencing a common objective reality. This cannot be proven but must be assumed.
Science is the attempt to describe, model, understand and quantify this objective reality. If it does not actually exist then such pursuits are invalid and worthless.
So:
Axiom 1: An external objective reality common to all exists.
Is this an axiom of scientific investigation?
Does anybody have any suggestions as to what other "axioms of scientific investigation" there might be?
As an ultimate, and very likely overly-ambitious, aim I would like us to define the set of unprovable, and often unspoken, assumptions upon which scientific investigation is founded.
This is definitely one for those with an interest in the philosophy of science so, if promoted, the 'Is it Science?' forum would seem to be the obvious place for it.