This site is an addendum to the Twitter Seminar LogicByTweets and displays its content in chronological order. Plus further explanations, discussions, references, etc.

With few exceptions, the original numbering of the posts is preserved. So is the seminar style.

If my time allows, I may publish the series as a book with better & more coherent editing later (very much later!).

Motivation: In November 2014 I was in bed with a heavy flu and came across a Logic Seminar on YouTube given by a German philosopher of science named Paul Hoyningen-Huene. People may know him as a disciple of Paul Feyerabend; he has no interesting work of his own. And I was veritably shocked. For hours, really: hours (!), he plays around with variables in conditionals without telling his students what that’s all about. I got up, shuffled to my bookshelves, and lo and behold, of course, there are good Logic books: W.v.O. Quine’s Philosophy of Logic, for instance, or Alfred Tarski’s Introduction to Logic and to the Methodology of the Deductive Sciences, or Patrick Suppes’s Introduction to Logic; not to forget Alonso Church’s Introduction to Mathematical Logic, and A. A. Stolyar’s Introduction to Elementary Mathematical Logic. All of them, are not too difficult to read and give, apart from their own particular ideas, perfect overviews of the significance of logic in the sciences and in everyday ‘experience.’

This convinced me that it should be possible to give an introduction to logic in accessible language. And since the kids are more on Twitter today than in the classroom, I thought a Twitter seminar could be just the right thing to do. So here is it. It does not presume any prior knowledge of logic, nor is any background in mathematics supposed. My primary intention is only this: Logic is fun! It’s not ‘dry’ at all, once you understand what it’s good for.

So enjoy!

* * * * *

PS: A colleague mentioned that speaking of “kids” in the preceding paragraph could sound disrespectful. This is by no means my intention. It’s rather meant in the sense of Pete Townshend’s The Kids are Alright (The Who, 1965): Always question authority! This applies to handed down philosophical truths as well. And with a good sense for logic you may be able to avoid a whole bunch of spurious philosophical problems. Think only of the ‘ontology’ of universals, or of ‘dispositions’ (even ‘intentions’) in things, yes, such is still around…

It’s up to you ‘kids’ to make better philosophy.

And if you run into errors—that’s alright too. Nothing really depends on philosophy, but all depends on Logic. Understand its basic rules & principles and then make up your own mind about the philosophical theories that cross your way. So there’s nothing to fear! (Except maybe your philosophy teacher…).

PPS: If you have questions, problems, doubts, whatever, concerning an idea of your own that seems to be new, i.e., that seems to lie beyond the beaten tracks of customary philosophy teachings, I am happy to support you. It depends, of course, on what it is and on my expertise in the particular case: LogicByTweets@hotmail.com. But please don’t bore me with hints at secondary literature you pick up from social media networks.

I am at Pittsburgh University, May 10-31, 2015.