““Our attraction to that quality which we have come to call 'beauty', and which we associate with the detection of innate unity and harmony in the face of superficial diversity, has led us to expect that the unity of the Universe should be expressed in certain particular ways. If we are physicists we might often hear talk of the 'beauty' or 'elegance' of particular ideas or theories to such an extent that, like Dirac, *we make aesthetic quality a guide or even a prerequisite for the formulation of correct mathematical theories of nature.””
