Hacker News: bitdiddle

New comment by bitdiddle in "Category Theory Illustrated – Logic"

bitdiddle — Sun, 26 Sep 2021 18:36:05 +0000

I think the general program of categorical logic, the work of Lambek and Scott, and J. Bell on topos theory and local set theory really make clear the relationship between category theory and logic, as well as lambda calculus.

A topos is essentially a cartesian closed category with a subject classifier. In Set this is the two element set of 1/0 which is a Boolean algebra and thus the internal logic of the category Set is classical.

In general though the subobject classifier is a heyting algebra which expresses the semantics of intuitionistic logic.

There is also a very good, but introductory, book by Goldblatt on Topoi that covers this logical aspect

So in terms of logics the category of Sets is the exception.

By internal logic I mean that for every topos one builds up a theory using it's objects and function between them. An equivalence theorem (see J. Bell) states that a given topos is essentially equal to the category generated by this internal theory.

This program began with Lawvere who noticed that conjunction and implication were really adjoints, the same one as between the product and hom functors in a cartesian closed category.

New comment by bitdiddle in "Manyverse – A social network off the grid"

bitdiddle — Wed, 22 Sep 2021 09:39:47 +0000

There's a new feature, rooms[0], that allows members to replicate with one another and stores nothing.

[0]: https://github.com/ssb-ngi-pointer/rooms2

New comment by bitdiddle in "My Lisp Experiences and the Development of GNU Emacs (2002)"

bitdiddle — Sun, 07 Jul 2019 14:55:31 +0000

> Of course a problem was that in 1984 the modern importance of free software wasn't really apparent.

Perhaps it wasn't apparent widely, but it was certainly clear to MSFT and IBM. IBM lawyers at the time refused to allow RMS to come speak at the Watson lab where I worked, because of his ideas about free software.

New comment by bitdiddle in "My Lisp Experiences and the Development of GNU Emacs (2002)"

bitdiddle — Sun, 07 Jul 2019 14:52:58 +0000

Dan Weinreb had a different take on the symbolics era and the MIT lab.

[1]: https://danluu.com/symbolics-lisp-machines/

New comment by bitdiddle in "Scuttlebutt, a Decentralized Alternative to Facebook"

bitdiddle — Fri, 20 Apr 2018 00:10:17 +0000

https://scuttlebuttbrewing.com/

New comment by bitdiddle in "Bitcoin Futures Will Be Allowed to Start Trading"

bitdiddle — Fri, 01 Dec 2017 13:12:40 +0000

According to Bloomberg, margin requirements are going to be quite high in order to keep bitcoin trading from creating issues.

If you can trade bitcoin futures in Chicago, to me that says regulation is coming, and even central bank involvement. Seems to go against the grain of what bitcoin pretends to be about.

Bitcoin Futures Will Be Allowed to Start Trading

bitdiddle — Fri, 01 Dec 2017 13:09:19 +0000

Article URL: https://www.bloomberg.com/news/articles/2017-12-01/bitcoin-futures-will-be-allowed-to-start-trading

Comments URL: https://news.ycombinator.com/item?id=15823551

Points: 3

# Comments: 5

IBM – Laying the Groundwork for Blockchain Domination

bitdiddle — Thu, 30 Nov 2017 15:43:07 +0000

Article URL: https://seekingalpha.com/article/4128098-ibm-laying-groundwork-blockchain-domination

Comments URL: https://news.ycombinator.com/item?id=15816562

Points: 1

# Comments: 0

Why Ageism Never Gets Old – The New Yorker

bitdiddle — Mon, 13 Nov 2017 11:55:04 +0000

Article URL: https://www.newyorker.com/magazine/2017/11/20/why-ageism-never-gets-old

Comments URL: https://news.ycombinator.com/item?id=15685832

Points: 2

# Comments: 0

New comment by bitdiddle in "An Open Letter to Intel"

bitdiddle — Tue, 07 Nov 2017 13:23:23 +0000

#2. Exactly, seems to me an academic kind of thing, he helped them a lot, a little attribution would not have hurt, and the lawyers could have easily been told to pipe down.

#3. It does offer the maximum freedom to some potential users, but no responsibilities to extend those freedoms to others. In my opinion this is why the GPL truly extends the maximum amount of freedom to everyone, users, lusers, abusers, and just plain old hackers.

[TYPES] Passing of Corrado Böhm – RIP

bitdiddle — Mon, 23 Oct 2017 12:45:39 +0000

Article URL: http://lists.seas.upenn.edu/pipermail/types-list/2017/001936.html

Comments URL: https://news.ycombinator.com/item?id=15532716

Points: 2

# Comments: 0

New comment by bitdiddle in "How the Elderly Lose Their Rights"

bitdiddle — Tue, 03 Oct 2017 17:00:35 +0000

yes, revocable and irrevocable trusts, combined with solid powers of attorney, living wills, etc..

Trusts essentially keep estates out of probate. Since it's the money these criminals are after they work well towards that goal.

New comment by bitdiddle in "How the Elderly Lose Their Rights"

bitdiddle — Tue, 03 Oct 2017 16:58:03 +0000

estate planning

New comment by bitdiddle in "Giving you more characters"

bitdiddle — Tue, 26 Sep 2017 22:46:12 +0000

It's all down hill from here. Pretty soon there will be a 2K word minimum and we'll all be making up stuff, like those fifth grade book reports.

New comment by bitdiddle in "Remacs – A community-driven port of Emacs to Rust"

bitdiddle — Sun, 16 Jul 2017 19:51:59 +0000

gotta love this line:

"We aim to be a drop-in replacement with bug-for-bug compatibility."

New comment by bitdiddle in "Mastering Programming (2016)"

bitdiddle — Fri, 07 Jul 2017 14:21:23 +0000

"30. In programming, everything we do is a special case of something more general -- and often we know it too quickly."

New comment by bitdiddle in "Introducing Increment"

bitdiddle — Thu, 13 Apr 2017 22:49:21 +0000

my thought exactly, memo to marketing :)

New comment by bitdiddle in "Daniel Dennett’s Science of the Soul"

bitdiddle — Fri, 24 Mar 2017 11:12:35 +0000

One of the best papers I've read on cartesian duality was by Vaughan Pratt[1] on Chu spaces. It's a little bit of a slog for those not conversant in foundations, but it does help ground the conversation in terms that are more rigorous.

As an aside, Chu spaces also provide a semantics for linear logic and are useful in understanding concurrency.

[1]: http://boole.stanford.edu/pub/ratmech.pdf

The RedMonk Programming Language Rankings: January 2017 – Tecosystems

bitdiddle — Fri, 17 Mar 2017 17:00:32 +0000

Article URL: http://redmonk.com/sogrady/2017/03/17/language-rankings-1-17/

Comments URL: https://news.ycombinator.com/item?id=13895653

Points: 11

# Comments: 0

Silicon Valley Takes a Right Turn

bitdiddle — Thu, 12 Jan 2017 11:12:53 +0000

Article URL: https://www.nytimes.com/2017/01/12/opinion/silicon-valley-takes-a-right-turn.html?ref=opinion

Comments URL: https://news.ycombinator.com/item?id=13381377

Points: 1

# Comments: 0