In this article I deal with the general question of logical truth or, rather, with the question of what it means when we say that a sentence or a judgement is true for logical reasons. I tackle this question against the background of the most important milestones in the development of logic understood in the broadest sense that is, the projects (1) of Eleatic and Platonic dialectic; (2) Aristotle’s syllogistic approach; (3) Kant’s transcendental logic; and (4) the modern logic of Frege. In relation to the latter I indicate two kinds of influence which formed it, namely (a) the mathematical influence stemming from the problems surrounding the reformed calculus, and (b) the philosophical influence consisting in the rejection of Kant’s definition of mathematics as sciences depending on constructions in space and time. The overall result of the paper will be a critical view of the very idea of formal logic, i.e. of the canon of judgement which is applied quite generally, regardless of the given field, so influentially articulated by, for example, Descartes and Brouwer.
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