## Compression

From a recent SMBC:

The punchline:

THe mouseover title: "Based on a conversation I had on twitter but couldn't find again! If you're out there, person I talked with, ping me and I'll post it."

The aftercomic:

(There's more — read the whole thing…)

In fact, 47 bits is quite a lot of information — the equivalent of more than 141 trillion equally likely alternatives:

2^47 = 140,737,488,355,328

So 47 bits could pick one set of attitudes and practices out of a very long list — if you had the contents of the list stored separately. Maybe these LGM have a suitably complex prior distribution, based on all the civilizations they've previously surveyed.

Still, without that list, 47 bits is not enough for the arrangement of atoms in a grain of dust, or of sounds in a second of music, or of letters in a newspaper article. Or of pixels in a comic — the png-compressed image for this SMBC is 703,626 bytes, or 5,629,008 bits. So we're probably OK, even without an interesting death.

1. ### bks said,

March 15, 2021 @ 8:11 am

"All of them agreed that the working-classes must be kept in their place; and all of them perceived that American Democracy did not imply any equality of wealth, but did demand a wholesome sameness of thought, dress, painting, morals, and vocabulary." –Sinclair Lewis (Babbitt)

2. ### Ross Presser said,

March 15, 2021 @ 11:58 am

47 bits could just be a hash of this woman's individual differences, used as an index into a much more complete table somewhere?

[(myl) Exactly.]

3. ### Gregory Kusnick said,

March 15, 2021 @ 3:04 pm

This is more or less the plot of Greg Bear's SF novel Eternity, in which aliens called Jarts ruthlessly reduce every world they encounter to its most compact representation in order to preserve the information for their remote descendants.

4. ### Andy said,

March 15, 2021 @ 3:43 pm

Is it just me, or is 'poom' a fairly obscure ideophone? As a native speaker of English, I've never seen it before. Also seems a little too close to 'boom' to be an obvious choice to describe the action of a gas?

5. ### J.W. Brewer said,

March 15, 2021 @ 4:26 pm

"Poom" seems like a blend of "poof" and "boom," so is maybe supposed to be evoke an event or action less violent than the latter but more so than the former?

6. ### Orin Hargraves said,

March 15, 2021 @ 5:05 pm

So it emerges that one great benefit of rising above cliché as often as possible is that we become less desirable candidates for compression.

[(myl) Indeed. And a non-trivial question: is psychotic discourse more or less compressible than its sane counterparts? I think it depends on the kind of psychosis, though I don't believe that the DSM has anthing to say about this question.]

7. ### Julian said,

March 15, 2021 @ 5:37 pm

This thread reminds me of xkcd's 'subway sheeple' cartoon:
https://xkcd.com/610/
The whole question of what reminds us of what is fascinating – nay, awe-inspiring.
As I dined on fish and peas the other night, one pea rolled off my plate. I *instantly* though of this Larson cartoon:
https://www.pinterest.com.au/pin/91268329924038125/
The amount of rubbish stored in the attic of our memory, essentially unrecoverable except in response to a suitable reminder, must be mind-boggling. Would 47 bits cover it?

8. ### J.W. Brewer said,

March 15, 2021 @ 8:07 pm

I am reminded of James McCawley's "Thirty Million Theories of Grammar" (a catchy title both as an essay/article and as the title piece in a book-length anthology of his writing). McCawley's claim, best as I can recall, was that there were at that point (way back during an unenlightening period of factional warfare in the discipline that is perhaps best not dwelt on in detail) at least 25 different issues on which a theorist of syntax could take one side or the other without their position one issue logically requiring them to take any specific side on any of the other issues. Two to the 25th power got you a bit over 30 million, as the range of theoretically possible overall points of view. From which it follows the LGM encoding syntactic theoreticians of that period would only need a maximum of 25 bits — except that's way way too many because of course the overwhelming majority of the theoretical positions suggested by McCawley's math were in fact held by no one.

9. ### EmilyPigeon said,

March 16, 2021 @ 12:01 pm

The after comic is literally the ending of a Borges story.

10. ### Martha said,

March 17, 2021 @ 3:16 pm

Andy – When I got to "poom," I thought that's what this post was going to be about.

11. ### Viseguy said,

March 23, 2021 @ 6:43 pm

After this, I'm determined to compress my estate plan — when I come up with one — into 47 bits. Because I have 2^47 cousins who would take in intestacy if my wife predeceased me. (First cousins are descendants of grandparents, and my paternal GF was born in 1845.)