Abstract
This essay addresses the problem of how to account for our meeting of minds, for our being able to linguistically express agreement regarding external events despite wild dissimilarity of our nerve nets. An explanation is provided based on the instinct of induction, the instinct of similarity, and natural selection. There are three networks at play in the meeting of minds: perceptual similarity, the intersubjective harmony of similarity standards and thus the relation structuring the intake of perceptions; implication, the relation expressed by the universally quantified conditional and structuring our system of the world; and class membership, the relation structuring the domain of pure mathematics.