[FOM] A textbook on logic with natural deduction

[Charles Parsons]

On Dec 2, 2009, at 3:06 PM, paul at personalit.net wrote:

> Dag Prawitz's two short pieces on natural deduction in A Philosophical
> Companion to First-Order Logic, edited by R. I. G. Hughes (Hackett
> Publishing, 1993), are excellent.
>
> E. J. Lemmon's excellent Beginning Logic book is also printed by  
> Hackett
> for under $20 -- better price than the $80 mentioned in a previous  
> post.
>
> Cheers,
>
> -paul
>

Lemmon's book is one that I used successfully when I last taught  
introductory logic, between 1980 and 1988. The fact that the  
expensive edition that George McNulty mentioned exists means that the  
Hackett edition is probably out of print. However, it is listed on  
Hackett's web site, so maybe it is available.

McNulty writes correctly that the book is "in the philosophic side,"  
i.e. aimed at the sort of course that is taught in philosophy  
departments. But it is unusual among such books, in that it doesn't  
ask the students to paraphrase arguments in natural language and  
determine their validity. In spite of its artificiality, I think  
that's important for philosophers but not particularly for  
mathematicians. (I think I sometimes combined Lemmon with Hodges's  
Penguin, which is excellent on the natural-language side, although  
written by a mathematician.)

One thing I especially liked about Lemmon's book is that one could  
see clearly what depends on what, in contrast with the book from with  
which I began the study of logic, Quine's Methods of Logic, in many  
other ways a masterpiece. For example, one can see clearly what in  
the rules forces the equivalence of 'if p then q' and 'not both p and  
not-q' and thus the truth-functional reading of the conditional.

Charles Parsons