Abstract (Stapp) Quantum Mechanics Rescinds the Classical Physics Underpinnings of the Materialist Conception of Man. An important impact of science upon our understanding of our own human role in the universe stems from the principle of "the causal closure of the physical". This principle asserts that the physical present is causally determined by the physical past. Such a principle, if true, would reduce us to mechanical automatons. That principle is indeed a basic feature of the classical physical theories that arose from the seventeenth century works of Galileo, Descartes, and Newton, and that reigned until the first part of the twentieth century, when they were eclipsed by quantum theory. Quantum mechanics introduced into the dynamics a fundamental element of uncertainty that destroyed the determinism of classical physics. But the entry of unchecked uncertainty is not philosphically helpful. However, quantum uncertainty is held in check by a process, von Neumann's process 1, that can be tremendously beneficial. In order to reconcile the basic microscopic uncertainties with the definiteness of our actual experiences, orthodox quantum mechanics introduces into the dynamics certain "free choices" attributable to human actor/observers. These choices have important physical consequences, but are "physically free" in the very specific sense that they are not determined in terms of physical properties by any currently known laws. This opening can be exploited to develop a quantum understanding of ourselves that is harmonious with our conception of ourselves as "free agents". This development paves the way to philosophical discussions that are strictly compatible with science, but not chained to the idea that man is, causally, merely a very complex but basically purely physical piece of machinery. This should have liberating effects upon our deliberations here in Doha.