What is largely beyond question, and is of primary importance to the journey
described in my book The Elegant Universe, is that even if one
accepts the debatable reasoning of the staunch reductionist, principle is one
thing and practice quite another. Almost everyone agrees that finding the
T.O.E. would in no way mean that psychology, biology, geology, chemistry, or
even physics had been solved or in some sense subsumed. The universe is such a
wonderfully rich and complex place that the discovery of the final theory, in
the sense we are describing here, would not spell the end of science.
Quite the contrary: The discovery of the T.O.E.—the ultimate explanation of
the universe at its most microscopic level, a theory that does not rely on any
deeper explanation—would provide the firmest foundation on which to
build our understanding of the world. Its discovery would mark a
beginning, not an end. The ultimate theory would provide an unshakable pillar
of coherence forever assuring us that the universe is a comprehensible
place.