Theory of Everything

David Lindley, The End of Physics. The Myth of a Unified Theory, 1993. From Chapter 9, The New Heat Death

We are already at the point where experiments are becoming impossible for technological reasons and unthinkable for social and political reasons. An accelerator bigger that the supercollider would be a vast technical challenge, and even if physicists are willing to try it, the likelihood of society paying the bills seems faint.

The physicists must hope instead that they can complete physics in the manner the ancient Greeks imagined, by means of thought alone, by rational analysis unaided by empirical testing. The ultimate goal in physics seems to demand, paradoxically, a return to old ways.

Perhaps physicists will one day find a theory of such compelling beauty that its truth cannot be denied; truth will be beauty and beauty will be truth – because, in the absence of any means to make practical tests, what a beautiful is declared ipso facto to be the truth.

This theory of everything will be, in precise terms, a myth. A myth is a story that makes sense within its own terms, offers explanations for everything we can see around us, but can be neither tested nor disproved. A myth is an explanation that everyone agrees upon because it is convenient to agree on it, not because its truth can be demonstrated. This theory of everything, this myth, will indeed spell the end of physics. It will be the end not because physics has at last been able to explain everything in the universe, but because physics has reached the end of all the things it has to power to explain.