Quantum Mechanics is Probabilistic in Nature

Elitzur (1991) maintained that my version of Schrödinger's cat gedankenexperiment does not provide the basis for demonstrating the effect of consciousness on the course of the physical world. The nature of the difference between Elitzur's and my views concerning the gedankenexperiment is discussed, and the key to this difference concerns the fundamentally probabilistic nature of quantum mechanics. Elitzur has failed to see that in quantum mechanics consciousness fundamentally is that through which the physical world is known. Elitzur's characterization of my thesis concerning consciousness and human observation as reflecting radical idealism is discussed. A second gedankenexperiment is noted in which the observer's circumstance, other than the time of measurement, is also a variable and which tests whether or not mind, or consciousness, has an impact on the course of the physical world.