How Propositional Language Created a New Plane of Human Existence

Gregg Henriques's Unified Theory of Knowledge (UTOK) makes a strong ontological claim: propositional language does not merely augment animal cognition — it inaugurates a genuinely new plane of existence, the culture-person plane. Building on Michael Tomasello's work on shared intentionality, Henriques traces a developmental arc from Joint attention and symbolic tagging to the Emergence of full propositional syntax. The critical threshold is the proposition itself — a structure that can be negated, questioned, and evaluated for truth value. Once propositions exist, the question "how do you know?" becomes possible, and with it, the demand for Justification.

This demand is generative in a precise sense: it produces Justification systems, which Henriques designates as Capital-C Culture. Law, religion, science, money, and political ideology are all networks of propositions that function to legitimate and delegitimate actions within social groups. To be a "person" in the UTOK framework is not merely to possess a self-conscious mind — it is to be constituted as an accountable agent on a social stage, where one's claims and actions must be defended through shared propositional structures.

The implications for psychology are far-reaching. If persons are partly constituted by the Justification systems they inhabit, then human psychology cannot be reduced to neuroscience or comparative animal behavior. The minded animal and the culture-person occupy ontologically discontinuous planes. A complete science of human behavior must therefore bridge into the social sciences, treating cultural Justification structures not as contextual background but as constitutive features of what it means to be human.