Abstract

Lewis Carroll in “What the Tortoise Said to Achilles?” questioning one of the most important basis of logic and by narrating a fanciful dialog asks why we should move from premises to the conclusion. Is logic itself enough to justify the use of logic or we need something beyond logic to do that. In this article, two main approaches have been considered. First, the logical approach which Bertrand Russell is its most important member, and second, the social-internalism approach which Peter Winch advocates. These two main philosophers have referred several times to Carroll’s article. According to Russell, analyzing logic is sufficient to explain why consequent will infer from premises, and on the other hand, Winch and his followers think every inference has a root in the historic understanding of life and if this understanding fails, logic will fall apart too. I will make some objections to both of these. In the end, I propose that the solution is to return to formal logic. If formal logic understood well, there won’t be any need to seek another logic to teach us how to use logic. Valid formal inferences are what logic consists of and if someone violates these inferences, he is out of the boundaries of logic.