Perhaps the problem is the seeming need that people have of making black-and-white cutoffs when it comes to certain mysterious phenomena, such as life and consciousness. People seem to want there to be an absolute threshold between the living and the nonliving, and between the thinking and the “merely mechanical,” ... But the onward march of science seems to force us ever more clearly into accepting intermediate levels of such properties.
‘Shades of Gray Along the Consciousness Continuum’, Fluid Concepts & Creative Analogies: Computer Models of the Fundamental Mechanisms of Thought (1995), 310.