The somewhat radical view of Penrose is often criticized for being based on the sheer assumption of quantum effects playing a role (Keith Stanovich, 1990). Besides of this lack of evidence argument, Herbert Simon (1995) argues that the quantum effects are to small to play a role on the macro level, because they are averaged out before they can affect higher-level processes. On the other hand Penrose is perhaps supported by some of the developments in quantum computing in which more coherence is attained. [Pen96] Semantic Analysis in AI has a tensor structure, which is uniquely suitable for quantum computation. If the mind entails a formal qunatum structure, this is not accidental [AC04].

Erik de Bruijn 2007-10-19