Frege and young Wittgenstein about the laws of inference. Afterword to TLP 5.132

Abstract

In my paper of 2017 written in Spanish, «Justification of Inferences. Frege and Tractatus 5.132» I argued, following Proops (2002) that Wittgenstein misunderstood Frege when affirming that he —as supposedly did Russell as well— relied on laws of inference to justify the conclusion from q to p. In this short paper, I first try to show that the ideas of Frege and young Wittgenstein concerning inferences are very similar, except for evident differences in the fundaments of their doctrines. I then give a rough picture of some aspects of the teachings of the Tractatus, which allow understanding better the critical remarks about Frege and Russell formulated in 5.132, not being the result of poor comprehension of their respective doctrines, but as a manifestation of the general incompatibility of their visions of logic. Giving voice, in particular, to the conviction that his teachers were not aware that propositions share the entire space of logic between them, not leaving any place for a thinker to assign them an arbitrary role according to his needs in proofs of logic.