My project introduces the principle of “Categorical Nash Equilibrium” (CNE), which integrates Kantian categorical imperative with the concept of Nash Equilibrium (NE) in game theory. The CNE posits an equilibrium state where each player's strategy aligns with the others, and no individual player is incentivized to change their strategy unilaterally. Importantly, it incorporates a moral dimension, invoking the Kantian notion of autonomy, where rational agents legislate their universally applicable moral rules, acting not out of self-interest but out of duty to reason. This equilibrium concept responds to challenges in economic methodology by bridging the gap between ethical imperatives and strategic decision-making. Through a methodological analysis of how moral thresholds can be integrated into economic models, this paper contributes to debates on collective action and sustainability.