I have been very distracted over the last week reading and re-reading IFL. The trouble with writing or tinkering with something like a logic textbook is that there is no obvious point where you should call a halt to the revisions. You can always make it just that little bit better. Even if it is merely changing a bit of punctuation to improve the structure of a sentence.

Still, on the whole, I’m quite enjoying the job. I certainly feel more warmly inclined to IFL than I did. But it has also made me want to rethink how I should run my first-year lectures based on the book. Our students are a bright bunch. Rereading IFL, it’s mostly extremely clear (although I say so myself!). Given the back-up of logic example classes, students can actually teach themselves a lot of stuff just from the book. This year, I think I’ll try using some of the lectures to range a bit more widely around and about what’s in the book itself. More fun for me and surely more fun for the audience.

AnonymousYour book really is very good. You answer my questions above directly and reasonably. I think the structure of your book is very good. It is helping me a lot. Thanks!

AnonymousBased on this post, I checked your logic text out of the library and I am enjoying it very much.

I am having trouble with “validity”. The intuitive definition you give on page 4 makes perfect sense to me, but we’ve been given another definition that confuses me, and I am trying to make sense of it all.

“It’s impossible for all of the premises to be true and the conclusion false”.

And we are told if the premises include a contradiction (cannot be true), and the conclusion is a tautology, then we can satisfy this definition.

And I can’t understand this.