Weak Equivalence Weak equivalence is a relationship between the outputs of two systems that are being compared. For example, human chess players and computer chess players are weakly equivalent, in the sense that they both play the game of chess, but use very different procedures to decide which move to make next in a game.
Weak equivalence is important in cognitive science in two respects.
First, it is the kind of comparison that the Turing test offers, which is why it is also sometimes called Turing equivalence. Second, although weak equivalence is necessary for validating theories in cognitive science, it is not sufficient. This later requirement is called strong equivalence. Computation and cognition.