Photograph by Jeff Wilson Steven Weinberg shared the 1979 Nobel Prize in Physics for a landmark act of unification: He found an underlying similarity between two of nature's four forces, electromagnetism and the weak force. Now at the University of Texas at Austin, he has a dozen honorary doctoral degrees to his name as well as several best-selling books. He even appears in Bartlett's Familiar Quotations. "The more the universe seems comprehensible, the more it also seems pointless," he wrote in his book The First Three Minutes. He continues to defend this view in his latest work, Facing Up: Science and its Cultural Adversaries (Harvard University Press, 2001.) Weinberg discussed the limits of knowledge with associate editor Josie Glausiusz.
You've worked towards a "final theory" of physics that would unify all of nature's forces. What would such a theory consist of? A final theory would be a scientific principle which explains gravity and all the other forces of Nature, explains why the quarks and the electrons and the neutrinos and all those other particles have the properties they have. It would be at the end of the chain of explanations.
