To my mind, the most fascinating thing about theorems of Bell’s type is that they provide a rare opportunity for an enterprise which can properly be called ‘experimental metaphysics
While we might expect the injection of philosophy into science to result in something less scientific, in fact, the opposite is true.

Experimental Metaphysics

Experimental Metaphysics is the physicist's revenge on pure philosophy that consists in settling a question not from the power of sheer thought but mainly by testing it in a laboratory.

Asking nature for answers is regarded as the birth of modern physics, with Galileo back in the 17th century. The biggest such breakthrough however was Bell's approach to EPR, through inequalities whose violation would decide whether quantum mechanics is complete or not, a point which had been argued (mainly between Einstein and Bohr) with, at best, Gedankenexperiments.

The term was first used by Abner Shimony[1]

The epitome of experimental metaphysics is Wigner's friend.

References

  1. Shimony, A.: Search for a worldview which can accommodate our knowledge of microphysics. In: Cushing, J.T., McMullin, E. (eds.) Philosophical Consequences of Quantum Theory. University of Notre Dame Press, Notre Dame (1989)