 The early Wittgenstein shares with Kant the idea that the logical expressions do not express meanings in the way that non-logical expressions do (see 1921, 4.0312). Consistently with this view, he claims that logical truths do not “say” anything (1921, 6.11). But he seems to reject conventionalist and “tacit agreement” views (1921, 6.124, 6.1223). It is not that logical truths do not say anything because they are mere instruments for some sort of extrinsically useful manipulation; rather, they “show” the “logical properties” that the world has independently of our decisions (1921, 6.12, 6.13). It is unclear how apriority is explainable in this framework. Wittgenstein calls the logical truths analytic (1921, 6.11), and says that “one can recognize in the symbol alone that they are true” (1921, 6.113). He seems to have in mind the fact that one can “see” that a logical truth of truth-functional logic must be valid by inspection of a suitable representation of its truth-functional content (1921, 6.1203, 6.122). But the extension of the idea to quantificational logic is problematic, despite Wittgenstein's efforts to reduce quantificational logic to truth-functional logic; as we now know, there is no algorithm for deciding if a quantificational sentence is valid. What is perhaps more important, Wittgenstein gives no discernible explanation of why in principle all the “logical properties” of the world should be susceptible of being reflected in an adequate notation.