Symbolic Logic (1897)

131 points by kritixilithos 5 years ago | 25 comments

bdefore 5 years ago |

What a glorious conclusion to the introduction:

"Mental recreation is a thing that we all of us need for our mental health; and you may get much healthy enjoyment, no doubt, from Games, such as Back-gammon, Chess, and the new Game “Halma”. But, after all, when you have made yourself a first-rate player at any one of these Games, you have nothing real to show for it, as a result! You enjoyed the Game, and the victory, no doubt, at the time: but you have no result that you can treasure up and get real good out of. And, all the while, you have been leaving unexplored a perfect mine of wealth. Once master the machinery of Symbolic Logic, and you have a mental occupation always at hand, of absorbing interest, and one that will be of real use to you in any subject you may take up. It will give you clearness of thought——the ability to see your way through a puzzle——the habit of arranging your ideas in an orderly and get-at-able form——and, more valuable than all, the power to detect fallacies, and to tear to pieces the flimsy illogical arguments, which you will so continually encounter in books, in newspapers, in speeches, and even in sermons, and which so easily delude those who have never taken the trouble to master this fascinating Art. Try it. That is all I ask of you!"

lioeters 5 years ago | |

Ah, Lewis Carroll. I see some of his works as a step in a long line of thought, from Renaissance philosophy, art and science. In particular, his approach to logic feels like a precursor and influence on books like Gödel, Escher, Bach.

The joy the author takes on conceptualization and mental operations, logic and computation; the willful use of the Imagination to explore and deepen understanding - there's irreverence, "just for fun", like a child working with the most fascinating toy of all - the mind - and at the same time, a respect and reverence to the profound insights, fruits of the work of play.

dmix 5 years ago |

I'm currently reading up on formal logic in order to fully understand Probability Theory by E. T. Jaynes [1] and I've found it difficult to find a good logic book. There's a thousand on Amazon and it's hard to tell which ones are written a century ago w/ re-released dates with old notation or missing some new ideas. An "original publishing" data feature on Amazon would be a godsend.

I've seen a few well reviewed Symbolic logic books but not sure if that fits the criteria. Mostly digging into boolean algebra atm.

[1] https://www.amazon.com/Probability-Theory-Science-T-Jaynes/d...

fmoralesc 5 years ago | |

I second the recommendation of checking the Teach Yourself Logic guides by Peter Smith, but I will give some more specific recommendations:

- Greg Restall - Logic (and he also gives some recommendations of his own that are worth checking out). If you use this, check the errata in Restall's website.

- Richard Jeffrey - Formal Logic: Its Scope and Limits (Smith has a textbook that is modelled largely after this, but Jeffrey's book is more to the point and fun to follow along)

- Daniel Velleman - How to Prove It, which has tons of good exercises for practicing symbolig logic in the context of the construction of proofs, and introduces some mathematics along the way.

dmix 5 years ago | | |

Thanks, I wasn't familiar with the "Teach Yourself" series, that's going to help me on my path learning math/stats/probability theory.

6AA4FD 5 years ago | |

I've used forall x (calgary remix), both the winter 2018 and the spring 2020 editions, and I found it quite good. It teaches truth functional and first order logic, and it's probably accessible to most high school graduates. I've seen it taught with good results to students of different academic backgrounds as a 'math' course for general education. I've linked it below and it's free (as in beer and as in freedom) so it's definitely worth glancing at, along with the rest of the open logic project.

http://forallx.openlogicproject.org/

nmadden 5 years ago | |

https://www.logicmatters.net/tyl/

bubblyworld 5 years ago | |

As a mathematician, I find this surprising - formal logic and probability theory don't usually have much to do with each other. Is the issue that you have trouble with formal mathematical notation?

dmix 5 years ago | | |

If you look at the probability book I mentioned it uses an algebraic boolean logic notation and basic set theory to build a formal theory of inference. The first chapter is an condensed introduction to the formal logic and notation used - which is what I was struggling with following some of the more complex equations.

Having read half a book on logic and subsequently learned basic set theory has already helped read the first portion of the probability book. But then I also got really into formal logic, I found it really fascinating as a programmer and I think every person should learn it (with plenty of applications to regular life), so I decided to take a deep dive into it. The venn diagrams visualizations are what helped me the most.

I think one of things that held me back initially was my background as a programmer, it made reading the logic set notation challenging, ie the plus signs meaning disjunctions and primes negation conjunctions.

BaronSamedi 5 years ago | | |

This reminds me of my wish to see a unified theory (and notation) that encompasses formal logic and probability. On their own, each is lacking. A unified system, for example, in which we have all the tools of first order logic and Bayesian probability would be very powerful.

auggierose 5 years ago | |

Try this one:

https://www.cambridge.org/core/books/handbook-of-practical-l...

Gormisdomai 5 years ago |

Here's an interactive website for trying the system out https://lewiscarrollresources.net/gameoflogic/demonstrator.h...

Does anyone know if this graphical reasoning system something Lewis Carroll invented himself?

It looks like he also wrote a sequel book, about how to turn the system into a game: https://archive.org/details/gameoflogic00carruoft/page/28/mo...

Unfortunately it hasn't been digitised as well as OP

mitchtbaum 5 years ago |

http://finitegeometry.org/sc/16/logic.html

https://en.wikipedia.org/wiki/Charles_Howard_Hinton

https://en.wikisource.org/wiki/Author:Charles_Howard_Hinton

analog31 5 years ago |

I read this when I was a kid. In addition to presenting logic, it's also a delightful read, because Carroll's examples are hilariously sarcastic.

danielam 5 years ago |

Joyce's "Principles of Logic"[0] is also worth a read in this vein. Also, Fred Sommers and George Englebretsen have done some interesting work with an updated version of term logic called term functor logic.

[0] https://archive.org/details/principleslogic00joycuoft

sweeneyrod 5 years ago |

A fun book, I especially like the bits about "Mr Venn's Method of Diagrams". Some of the examples are a bit questionable to a modern eye though, like the one with "No Jew is ever a bad hand at a bargain" as a premise.

earthboundkid 5 years ago |

Gutenberg.org is just so unreadable. It’s a damn shame that the classics of the ages are hidden on a website no one would choose to read on. Why is there no Penguin Books for the web?

JonathonW 5 years ago | |

I think what you're looking for is Standard Ebooks: https://standardebooks.org/

They don't have Symbolic Logic, though.

robin_reala 5 years ago | | |

I produce SE books, I’ll add it to my list.

082349872349872 5 years ago | |

Mark 'em up to your liking (at least that's my interpretation of 1.E.6) https://www.gutenberg.org/wiki/Gutenberg:The_Project_Gutenbe... Aloha

kd5bjo 5 years ago | | |

That licence only applies if you want to use the term “Project Gutenberg,” which is trademarked. As noted at the top of that page, the actual book text isn’t protected by copyright at all, and you can do anything you want with it,.

kev009 5 years ago |

My brain temporarily read "Symbios Logic (1997)" and I got excited for a good story

kristopolous 5 years ago |

Yes, this is That Lewis Carroll