 Neither von Neumann nor Dirac take awareness of the result by a conscious observer to be a necessary condition for collapse. For von Neumann, the location of the cut between the “observed” system and the “observer”is somewhat arbitrary. It may be placed between the system under study and the experimental apparatus. On the other hand, we could include the experimental apparatus in the quantum description, and place the cut at the moment when light indicating the result hits the observer’s retina. We could also go even further, and include the retina and relevant parts of the observer’s nervous system in the quantum system. That the cut may be pushed arbitrarily far into the perceptual apparatus of the observer is required, according to von Neumann, by the principle of psycho-physical parallelism.