As for the forces, electromagnetism and gravity we experience in everyday life. But the weak and strong forces are beyond our ordinary experience. So in physics, lots of the basic building blocks take 20th- or perhaps 21st-century equipment to explore. – Edward Witten
But the beauty of Einsteins equations, for example, is just as real to anyone whos experienced it as the beauty of music. Weve learned in the 20th century that the equations that work have inner harmony. – Edward Witten