If we explain (or judge) a fact, we connect it with another; such linking, in Tlön, is a later state of the subject which cannot affect or illuminate the previous state. Every mental state is irreducible: the mere fact of naming it—i.e., of classifying it—implies a falsification. From which it can be deduced that there are no sciences on Tlön, not even reasoning. The paradoxical truth is that they do exist, and in almost uncountable number. The same thing happens with philosophies as happens with nouns in the northern hemisphere. The fact that every philosophy is by definition a dialectical game, a Philosophie des Als Ob, has caused them to multiply. There is an abundance of incredible systems of pleasing design or sensational type. The metaphysics of Tlön do not seek for the truth or even for verisimilitude, but rather for the astounding.
Tlön, Uqbar, Orbis Tertius, Jorge Luis Borges