 Knowledge of truths is distinguished from these two kinds of knowledge of things. Knowledge of truths consists in pieces of knowledge that although they cannot be proven by experience are such that we nevertheless “see” their truth (1912 [1974: 74]). Examples of truths that can be known this way are logical principles, the principle of induction, and everything we know a priori. This taxonomy of kinds of knowledge, Russell believes, can account both for the possibility of non-propositional and propositional knowledge and at the same time retain the claim as to the primacy of the acquaintance-relation for knowledge.