IFL as a free download, two years on …

The second edition of my An Introduction to Formal Logic was originally published by CUP. It is now exactly two years ago today that I was able to make the book free to download as a PDF and also make it available as a very cheap paperback, thanks to the Amazon print-on-demand system. How have things gone?

As with the Gödel book I really didn’t know what to expect. But from almost the beginning, IFL2 has been downloaded about 850 times a month, and has sold very steadily over 75 paperbacks a month (with numbers if anything creeping up). Which, on the one hand, isn’t exactly falling stone-dead from the press. But, on the hand, given the very large number of philosophy students who must be taking Logic 101 out there in the Anglophone world, it isn’t an overwhelming endorsement either. However, you can’t please everyone: there isn’t much consensus about what we want from an intro logic book (which is why unwise lecturers like me keep spending an inordinate amount of time writing our own, despite the best advice of our friends …). Modified rapture, then.

So what now? IFL1 was truth-tree based. IFL2 uses a Fitch-style natural deduction system. The intro book I’d ideally write would cover both trees and natural deduction. That wasn’t possible within the CUP page budget. But those constraints are lifted. A PDF can be as long as I want; and in fact the marginal additional printing cost of expanding the paperback by fifty or sixty pages wouldn’t make very much difference to the price. So an expanded IFL3 is certainly a possibility. But do I actually want to write a third edition?

OK, I confess I’m tempted! Not at all because I think the world stands in desperate need of such a book, but because (very sad to relate) I’d actually rather enjoy the exercise of getting things into the best shape I can, before I hang up my expository boots. A plan for 2023? If the gods are willing.

And in Big Red Logic Book news …

Brief version: There is now a hardback version available of the second edition of An Introduction to Formal Logic: ISBN 978-1916906327. It should now be available to order from bookshops (as well as from Am*z*n and some other online sellers). It is priced at £20/$25, about the minimum possible. I’ve just got a sample copy and it is very decently produced.

Longer version: You’ll probably recall that I recovered the copyright of the second edition of IFL a year ago so that I could make the PDF freely available (a pretty small gesture in these difficult times, but every little helps). Lots of students, though, do prefer to work from a physical book: so I also set up an inexpensive print-on-demand paperback (to minimise the cost, that is Am*z*n only). 

Now, as I’ve said before, self-publishing has the downside that the word doesn’t get out to librarians via a publisher’s fancy catalogue. But in any case, in last year’s lockdown, and more recently too, librarians were rightly concentrating on improving their e-resources, so it didn’t seem the time to fuss too much about getting physical copies into libraries. However, things are slowly returning to something more like the old normality for library operations. So I have now arranged for ‘proper’ hardback copies — printed by Lightning Source who do small-run/on-demand printing for some academic presses — to be available for library purchase at minimum cost from, inter alia, standard library suppliers. So do please ask your friendly local university or college librarian to order a copy or two (emphasizing, if you need to, that this is a significantly changed book from the first edition). Online resources are all well and good, though problematic for some students: to repeat, at textbook-length, many — like me — do much prefer to have real books available!

Big Red Logic Book, no. 2 — a year on

And it is now exactly a year since the self-published version of the second edition of An Introduction to Formal Logic was published as a paperback. This sells about 75 copies a month, very steadily. Again, the figure strikes me as surprisingly high, given that the PDF has also been freely available all along — and that’s downloaded about 850 times a month. Some of the online support materials, like the answers to exercises, are quite well used too. All in all, pretty pleasing.

I occasionally get friendly feedback about the book: and it will be interesting to see if sales/downloads jump at the beginning of the new term/semester as one or two more lecturers adopt the book as a main text. I do hope so (if only because students shouldn’t be being asked to fork out $100 for second-rate course-texts!).

Still, there’s a lot about this book that could be better, so I really do want to have a third bash at an introductory logic text, and sooner rather than later. But I haven’t yet decided quite how to handle this. Something that is recognisably a third edition of the present book? Or, leaving this version out there as it is (apart from any needed corrections), a rather different, brisker book, requiring just a bit more of the reader?  Choices, choices …


Big Red Logic Books: now available in Australia!

Short version: paperbacks of An Introduction to Gödel’s Theorems,  An Introduction to Formal Logic, and Gödel Without (Too Many) Tears are now available from Amazon in Australia.

Slightly longer version: An Australian version of Amazon’s KDP print-on-demand service has been up and running since the beginning of the year. Initially, however, it couldn’t handle books in the format of the Big Red Logic Books. But (though they haven’t told authors!) I have just discovered in the last hour that the books are now available locally. The prices are set to the minimum possible (the fixed printing and distribution charges are higher in Oz, but I’ve set the royalties to zero to compensate).

So please spread the word Down Under. The books have been available as PDF downloads for a year, but there are quite a few who much prefer to work from printed books. And do tell local librarians (you might need to do a bit of explaining/cajoling too, as librarians tend to hold their professional noses over self-published books, and don’t approve of Amazon either! — but other publication routes would have been much more expensive).

I’d be interested to hear how the physical copies turn out  (the UK printed ones are really surprisingly good, apart from slightly flimsy covers, given the price point).

New look, new hardback

The three Big Red Logic Books have a new look. I’m staying with the red theme, but no longer using the free Amazon KDP online cover-builder which produced their rather muddy colour and muddy swirls. The outsides, then, are a bit less dull. I’m afraid the insides of the paperbacks stay just the same!

More importantly, perhaps, a hardback of Gödel Without (Too Many) Tears is published today. It is currently available from e.g. Barnes and Noble (in the US), Gardners (the UK library book suppliers), Booktopia (in Oz), as well as the local Amazons. I hope it will soon propagate to other sellers like Blackwells. It won’t just appear on bookshop shelves, however: you’ll have to order it.

I’m not really expecting anyone reading this blog to buy it for themselves! However, you might like to recommend the hardback to your local friendly university or college librarian. Some librarians are pretty resistant to buying from Amazon (especially self-published paperbacks). That’s why I’m experimenting with hardback publication. We are going a step up here, using the same print-on-demand providers now used e.g. by CUP for some of their books, with a “proper” ISBN officially assigned to the Logic Matters imprint. It is still pretty cheap as academic hardbacks go — £14 in the UK and comparable prices elsewhere (so this isn’t going to make my fortune: to be honest, I’ll be pretty surprised if I even recoup the set-up costs.)

Of course the PDF version is still freely available, and I’ve kept the paperback version as Amazon-only as that absolutely minimizes the price to students. But I like to think that the book should be available on the shelves in university libraries, so please take a moment to recommend the hardback! Its ISBN is 978-1916906303. 

(Apologies by the way to readers down under that the paperback is still not locally printed and hence not cheaply available to you: Amazon say they are working on being able to produce paperbacks in the relevant format “soon” …)

Update: At the moment Amazon UK are giving a very long delivery date for the hardback, but I hope that’s temporary. Amazon US by contrast are giving a relatively short delivery date.

Not the podcasts

I was so tempted by the idea of recording podcasts to accompany IFL. After all, that is a longish book — well over 400 pages, with 42 chapters. There is a lot of signposting as we go through.  But I thought that some student readers might still appreciate a series of orientating chats, giving relaxed introductions to some main topics, which could be listened to over a coffee before tackling chapters from the book. 

But on second thoughts podcasts were of course a dumb idea. We very soon have to start juggling with symbols in logic — and how can we do that in a podcast, without being able to use a blackboard or whatever? A bit of experimentation suggested that the audio format wasn’t going to work very well (even if I included instructions like “look at page 123”). So I’m going to compromise. Yes, we want something that is as relatively informal as a podcast, which is still relaxed, short and snappy. But we also want to be able to use some symbols, or eventually state theorems which you might need to look at twice to understand; so we need  something bite-sized but text-based. Call the compromise a ‘logicbite’ — with an admiring nod to that wonderful series of philosophybites podcasts.

I’ve made a start, and the first five seven logicbites are now online here. They’ve developed in a way I didn’t really plan or predict — but rather than summarize my own words in my own words, I’ve found myself giving quotes (sometimes extensive ones) from other textbook authors, introducing key ideas in their wordsIt is always good for students to hear more than once voice.

And if I quibble with the quoted authors (especially in Logicbite 4, at some length), that’s not because I want to be particularly captious. Rather it is good for students to see it isn’t easy to get things spot on. We want to encourage students to read even logic texts — including mine! — with a sharply critical eye. Anyway, I hope some will find the logicbites useful. (At the moment IFL is being downloaded over a thousand times a month, so I guess some students out there are indeed being directed to it.)

A few thoughts about self-publishing

A very enjoyable walk down to my favourite library, the Moore library, in the winter sun. But not, sadly, to then read and write, and think, and idly look out of the windows, and take a coffee break, and write again. It will be a good while yet before all that is possible. I was just donating, via their dropbox, copies of IFL2 and GWT.

Time for an update, perhaps. How have things gone since I got the copyright back from CUP, and have been able to give away IFL2 and IGT2 as freely downloadable PDFs? I’ve just checked: since late August, IFL2 has been downloaded over 3.6K times. And after a quite crazy initial flood (when someone posted a direct link at Hacker News, without saying that the link was to a full book!), IGT2  has been downloaded another 4K times. The two books have sold well over 200 each of the inexpensive print-on-demand versions. (It is very early days for GWT … I’ll report back on that in the New Year.)

I didn’t at all know what to expect. Or rather, I was expecting something like that ratio of freely downloaded PDFs to bought copies: but I had little idea how many would be tempted by the books overall. I guess I am pretty pleased.

And it certainly seems to have been worth the small effort of making the print-on-demand versions available. I did ask online, and got enough responses to suggest that there is a significant minority of readers who significantly prefer to work from “real” books as opposed to onscreen PDFs (which is one reason that libraries should have hard copies available); and some of that minority said that they are prepared to pay a modest amount to get the hard copy too. And so it has turned out.

By the way, as I’ve remarked before, I wasn’t thrilled to bits to be using the Amazon-provided service. But for this kind of enterprise, it does seem the best and easiest option on various counts. And since sales are small, and I’ve only rounded up the price from the minimum possible by pence (in order to cover costs of getting proof copies, sending copies to copyright libraries etc.), you are at least not adding much to Amazon’s grossly undertaxed profits by buying a copy.

In some respects, then, isn’t this an ideal way of publishing book-length projects? Provide freely downloadable PDFs; and make as-inexpensive-as-possible print-on-demand copies available.

Well yes, but only up to a point. It works if you e.g. already have a book or two to your name and you don’t particularly need the imprimatur of a respected academic press for people to think that your book might be worth taking seriously. And if you don’t need that imprimatur for promotion purposes either. And  if you can find enough friends and acquaintances to give honest critical feedback at key writing stages (eventually doing the work of a publisher’s readers). And if you know your way around a document processing package like LaTeX well enough, and have a good enough design eye, to produce pages which look professional.  And if you can find enough other friends and acquaintances who will happily check for typos and thinkos (doing the work of a publisher’s proof-reader). And if you have enough internet presence via a blog or whatever to get the word out there beyond the small circle of those friends and acquaintances!

That’s quite a few rather big “if”s.

So traditional publishers do still have a role to play. Or at least some of them. Mind you, we can all think of publishers like Spr*ng*r where the quality control is minimal, and unheralded books (published at ludicrous prices) fall stone dead from the press. However, you can these days publish with an academic publisher and negotiate to be allowed to keep a PDF freely downloadable (some even put e.g. chapter-by-chapter PDFs open access on their website). CUP, OUP and MIT seem to allow this sort of thing sporadically, though I’m not sure what the principles of choice are. And then there is e.g. the very promising new BSPS Open initiative: the plan is to publish open access monographs under the supervision of an editorial board to maintain quality. It will be interesting to see how initiatives like that develop over the coming few years: for surely, with the gross pressure of costs on libraries (let alone the impoverishment of young academics) the days of publication solely by the £80 monograph must be numbered …

Meanwhile, if it can work for you, I can recommend the self-publishing route!

Free introductions to formal logic?

Browsing through, I notice that  The Logic Book by Bergmann, Moor and Nelson is $51 on Amazon.com. Not exactly cheap for a student.

Oh hold on, that is the price to rent the book for one semester. To buy it, even at Amazon’s discounted price, is $128. Ye gods. That’s simply outrageous, isn’t it?

What about the competition? Hurley and Watson’s Concise Introduction to Logic is $32 to rent for a semester, and $86 to buy (discounted from a ludicrous list price of $182). Copi’s Introduction to Logic apparently marches on to a 15th edition which you can rent for a price-gouging $79 (yes, you read that right: seventy nine dollars to rent the book for one semester): which makes buying it seem quite the bargain at $104 (reduced from an absurd $195).

I could go on. And it isn’t as if those books are (by my lights) particularly good, even if much used and recommended. Nick Smith’s Logic: The Laws of Truth by contrast is excellent; but although it has been out over eight years, it has never been paperbacked by Princeton, and has a list price of $62 ($56 on Amazon). Much better value, but still quite punchy for a student budget.

Which prompts the question: what books are there at this level — intro logic books aimed at philosophy students — which are free (officially free to download), and/or available for at-cost print on demand (for a student who prefers to work from a traditional book).

Here’s what I currently know about. We should probably set aside Neil Tennant’s Natural Logic (here’s a scanned copy from the author’s website), as this is tough going for beginners. So, in chronological order, we have:

  1. Paul Teller, A Modern Formal Logic Primer (originally Prentice Hall, 1989). Now available as scanned PDFs, with exercise solutions too, from this webpage for the book. Old but has some good features, and is very clearly written.
  2. Craig DeLancey, A Concise Introduction to Logic (SUNY Open Textbooks, 2017). Webpage for this book. Not to my taste, in either the order of presentation of material or the style of natural deduction system.
  3. P. D. Magnus, Tim Button and others, forallx (The Open Logic Project, frequently updated). Webpage for 2020 Calgary version. Available also from Amazon print on demand. Excellent.
  4. Peter Smith, An Introduction to Formal Logic (2nd edition, originally CUP, 2020) Webpage here. Available also from Amazon print on demand. Doesn’t cover as much and more expansive than forallx, so perhaps more accessible for self-study.

But there must surely be other options. I haven’t done a significant amount of homework on this, so do let me know what’s out there, and I will put together a web-page resource with links and more comments.

Big Red Logic Book, no. 2

Exciting headline news. Like the Gödel book, IFL2 is now available as a freely downloadable PDF. There is also an inexpensive Amazon print-on-demand book, for those who want a hard copy. UK link; US link. (Find on your local Amazon by using the ASIN identifier B08GB4BDPG in their search field.)

My apologies to anyone who bought the book at full price recently; but it was a surprise to me too that new publication arrangements became possible. Since I’m more interested in spreading the logical word than in totting up a few royalties (authors of logic books stand to make a fortune, of course …), I’ve decided to give the book away, or to provide access to a hard copy within a few pennies of the allowed Amazon minimum price. It’s a quite rotten time for students; so giving free/cheap access to decent learning materials when we can seems especially appropriate now. (Anyone thinking of using the book as a course text can be assured it will remain free.)

As I said about the Gödel book, the print-on-demand version is very decently printed, at least by Amazon’s UK printer, but the cover isn’t as good as a trade paperback’s (I don’t just mean the design, but the way it lies), and the binding is a bit tight. But on the other hand, it is a third of the price of the original, so I don’t suppose anyone will complain too loudly.

A reminder: The first edition of IFL concentrated on logic by trees. Many looking for a course text complained about this. The second edition, as well as significantly revising all the other chapters, replaces the chapters on trees with chapters on a natural deduction proof system, done Fitch-style. Which again won’t please everyone! So the chapters on trees are still available, in a revised form, here on the website. But it was considerations of space in the printed version that led to the relegation of (versions of) those chapters to the status of online supplements. This was always a second-best solution. Ideally, I would have liked to have covered both trees and natural deduction (while carefully arranging things so that the reader who only wanted to explore one of these still has a coherent path through the book). With e-publication, the question of length isn’t so vital. So over the coming months, I may be inclined to revert to the inclusive plan, and so eventually produce a third edition. We’ll see. IFL3 is for the future. For the moment, enjoy the delights of IFL2!


Thirty-six of the chapters in IFL2 have end-of-chapter exercises. Thirty-one of these  sets of exercises now have on-line answers, often with quite detailed discussion, available here. That includes all the chapters up to and including the chapters on QL proofs.

The question sets are also available online, in a form that means that most of them can be used independently of the book. Indeed from the download stats pre-publication, they already seemed to being so used, which is good to see.

Something else I recently discovered from those stats is that in fact the sets of exercises and worked answers I started for the Gödel book (which I stopped developing because I thought there was no interest in them) are in fact being downloaded quite often. So once all the IFL2 answers are all in place, I might yet turn back to putting together more Gödel-related exercises, which could be quite a fun project at least for the later parts of the book.

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