
Second-order logic explained in plain English - shawndumas
http://lambda-the-ultimate.org/node/5170
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danbruc
It avoids mathematical formulas, okay, but that doesn't make it plain English.
I read the first sentence at least three times and I am still not absolutely
sure that I didn't miss something and it says something (slightly) different
then I think.

I then only read a couple of sentences every couple of pages and the
impression I got was that it is essentially as technical as any axiomatic
definition just without the clarity and compactness of mathematical formulas.

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fenomas
Shouldn't this be pointing to the paper being discussed?

[https://www.academia.edu/11975482/Second-
order_logic_explain...](https://www.academia.edu/11975482/Second-
order_logic_explained_in_plain_English_)

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inetsee
If you would like to download the paper without having to sign up to
academia.edu, the abstract and a download link can be found here:
"[http://philpapers.org/rec/CORSL-3"](http://philpapers.org/rec/CORSL-3").

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konz
Your link seems to be broken (due to a trailing %22). This one works:
[http://philpapers.org/rec/CORSL-3](http://philpapers.org/rec/CORSL-3)

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inetsee
Sorry. I've put links inside double quotes before, but this is the first time
the second double quote has been tacked onto the link.

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richmarr
Maybe I'm being picky, but I interpreted the title to mean "explained in [less
that 75 pages of] plain English".

Attention span... draining... strength... procrastination fading... closing...
tab

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fenomas
15 pages. The document excerpt starts from page 61.

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IanCal
> No matter what human action you consider, if everyone does it to everyone
> doing it to them, then everyone has it done to them by everyone to whom they
> do it

I'm finding this incredibly hard to parse, yet feel like the point should be
quite simple, and the paper seems to get harder from there.

> if every given proposition bears it to every proposition bearing it to the
> given proposition, then every given proposition is borne it by every
> proposition the given proposition bears it to.

I don't want to knock someone's efforts at this, but perhaps this is only a
"plain english explanation" to someone who already understands the topic at
hand?

In all, it reminds me of "the missile knows where it is":
[https://www.youtube.com/watch?v=bZe5J8SVCYQ](https://www.youtube.com/watch?v=bZe5J8SVCYQ)

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Rangi42
Try substituting a particular action like "hit." It becomes easier to imagine:

> If everyone hits everyone who hits them, then everyone is hit by everyone
> whom they hit.

Or: "If everyone hits back, then everyone gets hit back."

The other example is the same, but with propositions instead of people and
"bearing" instead of hitting/unspecified human actions.

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IanCal
Thanks, that is clearer.

