  Ward does, at any rate, vehemently reject Clifford’s specific version of panpsychism. Clifford speculated that each atom of matter was associated with a quantum of experience, a small piece of ‘mind-stuff.’ This piece of ‘mind-stuff’ was conceived as an atom of experience, amounting to something less than a complete thought or feeling. Clifford also held that thoughts and feelings could be constituted simply by way of combination. “When molecules are so combined as to form the brain and nervous system of a vertebrate,” he wrote, “the corresponding elements of mind-stuff are so combined as to form some kind of consciousness.” Analogously, “when matter takes the complex form of a living human brain, the corresponding mind-stuff takes the form of a human consciousness, having intelligence and volition” (65). In this way, Clifford believed, it would be possible to explain why the genesis of complex material structures in the course of evolution is accompanied by the parallel emergence of higher forms of sentience and mental activity.