
Logic – Deductive and Inductive (1898) - mindcrime
https://www.gutenberg.org/files/18440/18440-h/18440-h.htm
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JasonFruit
Another excellent book — notably better, I'd say — on the same topic is
William Stanley Jevons' _Elementary Lessons in Logic, Deductive and Inductive_
[1]. It's written with simplicity and clarity, without any showing off of
terminology for its own sake.

[1]:
[https://archive.org/details/elementarylesson00jevo/page/n4](https://archive.org/details/elementarylesson00jevo/page/n4)

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ineedasername
If we're talking about inductive reasoning then it may pay greater dividends
to go to a primary source that really set the stage for everything that came
after him. This is David Hume in the form of his _Treatise on Human Nature_
[0]

[0]
[http://www.gutenberg.org/files/4705/4705-h/4705-h.htm](http://www.gutenberg.org/files/4705/4705-h/4705-h.htm)

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andrepd
This book predates many important developments of the 20th century. I'd say
its value is nearly zero nowadays, except from a historical standpoint.

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dwheeler
I agree, this document is really only useful for historical development.

However, it _is_ useful for tracking down some history. I've been trying to
track down this expression: "All men are mortal; Socrates is a man; therefore
Socrates is mortal". It's often quoted, but no one gave me a _source_. Using
this old book I managed to track it back to at least _A System of logic..._ by
John Stuart Mill, 1843, Book II Chapter 3 page 245.
[https://archive.org/details/systemoflogicrat01millrich/page/...](https://archive.org/details/systemoflogicrat01millrich/page/244)
The quote may be even older, but that was still a help.

If anyone knows an older source, I'd love to know. But that at least helped.

Anyway: while this document is only useful for its historical connection, as a
way to investigate the history of logic it's interesting.

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tunesmith
What a great snippet of info to know, thanks for posting this. I often use
that syllogism as an example for some visual logic software I'm writing.

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whatshisface
> _Mathematics treats of the relations of all sorts of things considered as
> quantities, namely, as equal to, or greater or less than, one another._

This was not actually true when this book was written: Euler's formula was
discovered in 1748, which I would consider evidence that complex numbers were
broadly "around" at least a century before 1898. Complex numbers are not
ordered, (for example, is 1 less than or greater than _i_?), so this claim
about math isn't right.

> _But, as we have seen, Logic does not investigate the truth,
> trustworthiness, or validity of its own principles; nor does Mathematics_

It does now!

> _As a Regulative Science, pointing out the conditions of true inference
> (within its own sphere), Logic is co-ordinate with [...] (ii) Æsthetics,
> considered as determining the principles of criticism and good taste._

It is funny now that people would study up on logic so they could prove to
their colleagues whether or not the latest production at the local theater was
any good.

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JasonFruit
Your comment seems determined to take the least charitable possible
interpretation of the material from the first few pages of the book. I'm sad
that you chose not to engage with the value it could provide.

~~~
whatshisface
Least charitable? There's no way that the author could have been expected to
anticipate how logic would develop over the next century, I'm just looking at
it from a modern perspective.

