Are quanta real?

the long version

"The central question at the Solvay Congress in 1927 was: Is quantum mechanics a "complete theory," or is the statistical character of its predictions merely the reflection of our ignorance of an underlying causal infrastructure? Today, after forty years of unchecked success of quantum mechanics on every front of physical science, the question still occupies the minds of many thoughtful students of quantum mechanics ... With a few exceptions destined for the specialist, all of this dialogue can be read and understood by anybody with sufficient interest in the epistemology of modern science. Many of the passages used are more or less faithful reproductions of actual conversations or statements from correspondence and published material."--The Introduction.