Fungibility does not imply liquidity, and vice versa. The limits of fungibility&colon; Relational schemata and the value of things. One of Brecht's earlier works, it explores themes of war, human fungibility, and identity. The fungibility of savings from debt service makes such claims difficult to establish. The game's themes included human psychology, renewal, and fungibility on the morality spectrum. Fungibility is also important within the context of product liability.