 Why do we not see any advanced waves in nature? Wheeler and Feynman (1945) came up with an answer. If we assume, they said, that radiation from an isolated accelerated charged particle is equally retarded and advanced, that is half retarded and half advanced to be exact, we can explain why it appears to be fully retarded in terms of the influence distant absorbers make on the source. The absorber consists of charged material that reacts with the source field by radiating with half retarded and half advanced waves. It is this half advanced field of the charged particles of the absorber which is added to the half retarded field of the source. The advanced waves of the absorber interfere constructively with the retarded waves of the source, whereas the same waves cancel out the advanced waves of the source in a destructive interference. Thus one of the consequences of Wheeler and Feynman Absorber Theory is the idea that emitters are intrinsically symmetric, another is that there is no intrinsic difference between so-called emitters and so-called absorbers. In other words, if this theory is true we have to conclude that radiation from a source is a time symmetric process but the presence of an absorber makes it asymmetric.