A common view among quantum theorists is that an object prior to measurement or observation can be said to exist only as simu ltaneous incompatible possibilities expressed as a wavefunction. Werner Heisenberg, one of the fathers of quantum theory, insisted that material reality must be conceived on two levels, potential and actual.
Material reality exists only potentially until rendered actual by observation.
But there is no consensus on the basic question of what counts as the crucial measurement or observation. In one interpretation, associated with, for instance, Von Neumann, Wigner, and Stapp, consciousness is crucial. The subject is conceived as an aspect of mind, and mind is conceived in terms of states or properties of some physical system. This conflation is at the root of many of the most p erplexing problems in the philosophy of mind and consciousness studies. Let it refer to anything anyone might be aware of or pay attention to.