Participation refers to a non-sensory unity between the perceiver and the representations. In this context, Barfield argues against a common view that says 1) the phenomena or representations of primitives are just like ours, and 2) the primitive differs from us in primitively theorizing that spirits are the cause of phenomena. The primitive in that common view is a sort of baby scientist just starting out who comes up with childish, superstitious causal explanations. Barfield disagrees with this portrayal of the primitive mind, citing anthropologists Émile Durkheim and Lucien Lévy-Brühl to the effect that primitive people do not perceive the world in the same way as moderns, nor do they propose spirits in an explanatory way as causes. Rather, primitives live in a world of "original participation," where the phenomena are not perceived as mere "things" separate from each other and from the perceiver. Instead, the primitive is aware of a non-sensory link between himself and the representations, and of the representations among one another. He has barely begun to do "alpha thinking," i.e., the modern person's detached thinking about the representations that tends to isolate them from himself and from each other. The primitive does not use the idea of spirits as a causal explanation of phenomena: in some sense he actually perceives non-sensory elements in the representations, whereby he participates the representations and they participate each other.
Primitive people’s behavior towards the world (as exemplified for example in totemism and animism in ancient literature, artwork, and philosophy) entails above all a different kind of "figuration"—not a primitive alpha thinking applied to the same kind of figuration as that of moderns. The first three chapters of the book focus on the fact that we still participate in the representations, although it is mostly unconscious for us today. Barfield emphasizes that it is no part of his purpose to advocate a return to the primitive's "original participation." He explores how our type of figuration grew out of the primitive type, and can evolve further toward a new form of figuration which he calls "final participation." More generally, the book is concerned with the evolution of consciousness over the last three thousand years.