Physicsts Must Also Be Philosophers.

Einstein, in his Physics & Reality, says that physicists must also be philosophers:

It has often been said, and certainly not without justification, that the man of science is a poor philosopher. Why then should it not be the right thing for the physicist to let the philosopher do the philosophizing? Such might indeed be the right thing at a time when the physicist believes he has at his disposal a rigid system of fundamental concepts and fundamental laws which are so well established that waves of doubt can not reach them; but it can not be right at a time when the very foundations of physics itself have become problematic as they are now. At a time like the present, when experience forces us to seek a newer and more solid foundation, the physicist cannot simply surrender to the philosopher the critical contemplation of the theoretical foundations; for, he himself knows best, and feels more surely where the shoe pinches. In looking for a new foundation, he must try to make clear in his own mind just how far the concepts which he uses are justified, and are necessities.

And by being its philosophers, he does not mean being its undertakers; for, as Étienne Gilson observed, philosophy "always buries its undertakers." Hence the necessity for a Thomistic revival in modern mathematical physics, Thomism being the philosophical foundation of modern science.