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6 month read-through/discussion of Gödel, Escher, Bach starting 1/17 on Reddit

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Re: 6 month read-through/discussion of Gödel, Escher, Bach starting 1/17 on Reddit

#81

Post by zinkem »

haberman wrote: post #73
zinkem wrote: post #68

Earlier quoted context omitted.

He's discussing our perception of the tones, you might want to check out this entry on wikpedia to understand what he's referring to: http://en.wikipedia.org/wiki/Shepard_tone This is a common concept in music synthesis, as you can create an endlessly rising 'melody' by repeating only 1 octave of some properly constructed timbres. This is the 'strange loop' he's referring to.

Bach's canon is not a Shepard tone. A Shepard tone would have been a more credible example of a "strange loop" than Bach's canon. But "Godel, Escher, Shepard" doesn't have the same ring to it.

He actually does discuss Shepard Tones and the Shepard Scale in the book, and explains how he thinks they are related to Bach's compositions.

Near the end of chapter 20, there is an example of a harmony that, when looped, creates the illusion of an endlessly rising melody.

In this harmony, the loudness of each note in the melodies rises and falls so that the lower melodies feed into the the higher melodies and ultimately fade out. In our brains, we hear this as an endlessly rising melody.

Re: 6 month read-through/discussion of Gödel, Escher, Bach starting 1/17 on Reddit

#82

Post by dangrossman »

yahelc wrote: post #63
dangrossman wrote: post #36

Earlier quoted context omitted.

Growing trees to make them into timber, pulp, etc. takes CO2 out of the atmosphere. As long as you're not growing them to burn them, it's one of the most effective CO2 sequestration methods we have. 77% of tree usage in the US is for timber and pulpwood. Fast-growing species are planted and harvested over a 10-20 year cycle so that as each section is cut down and replanted, another section is maturing. It's both sust…

[citation needed]

It's really not. If you want a citation for "growing trees takes CO2 out of the atmosphere", a high school bio book will suffice -- the carbon mass of the tree is carbon extracted from the atmosphere (and dead plant mass in soil, but the carbon there came from the atmosphere too).

If you want a citation for growing trees for timber and pulp as an effective CO2 sink, the citation is right in the grandfather post (an international climate change study by the IPCC including researchers from over a dozen countries, how much more authoritative can we get?), or just look up the paper and timber industries on wikipedia.

Re: 6 month read-through/discussion of Gödel, Escher, Bach starting 1/17 on Reddit

#83

Post by jerf »

presidentender wrote: post #38

I loved GEB, but since reading it (and jumping in and re-reading parts here and there when it strikes my fancy) I've come to the conclusion that it's a perfectly laid Dunning-Kruger trap which specifically ensnares people like me. I am not as smart as Hofstadter, and I know it, and so I'll never be sure I've actually understood the meat of the message. I think I get strange loops, recursion, self-reference and the me…

"I still think I'm missing something with breaking the record players, but based on my understanding it's a metaphor for incompleteness."

The record player is a Turing Machine interpreter. The "blowing up" is going into an infinite loop, or stopping the record incorrectly when it would have in fact terminated. The record player doesn't blow up if it A: runs a terminating program or B: correctly stops the record by determining the program will never halt. The differing record players represent the fact that you can write interpreters that will detect certain cases of infinite looping, but the halting problem prevents you from catching all cases. The repeated sequence in the book is:

1. A new "guaranteed safe!" record player is produced 2. A record is produced which breaks it (a program that loops but gets past the player is produced) 3. Goto 1.

At least, IIRC, it's been a few years since I read it.

Re: 6 month read-through/discussion of Gödel, Escher, Bach starting 1/17 on Reddit

#84

Post by Angostura »

drewrv wrote: post #57
funkah wrote: post #48

Earlier quoted context omitted.

Have you ever seen Hofstadter try to summarize the idea conveyed in the book? He really is not able to, and so I think the book pretty much boils down to "hey here's a bunch of weird/cool stuff." Which is not such a bad thing. But for me, there was a point where I had to stop reading, I think when he tries to independently derive propositional logic or something like that? (It has been a while.) I just remember findi…

He's pretty explicit that the idea is: consciousnesses is a strange loop, and since it's sometimes impossible to understand a system from within that system, we may never be able to understand the human mind because we are trapped within human minds.

See also: "The Emperor's New Mind" - 'Consciousness is a quantum phenomenon since they're both really weird".

Re: 6 month read-through/discussion of Gödel, Escher, Bach starting 1/17 on Reddit

#85

Post by yahelc »

dangrossman wrote: post #82
yahelc wrote: post #63

Earlier quoted context omitted.

[citation needed]

It's really not. If you want a citation for "growing trees takes CO2 out of the atmosphere", a high school bio book will suffice -- the carbon mass of the tree is carbon extracted from the atmosphere (and dead plant mass in soil, but the carbon there came from the atmosphere too). If you want a citation for growing trees for timber and pulp as an effective CO2 sink, the citation is right in the grandfather post (an i…

I was more interested in the source for the specific number you gave. Should have been less snarky, sorry!

Re: 6 month read-through/discussion of Gödel, Escher, Bach starting 1/17 on Reddit

#86

Post by dangrossman »

yahelc wrote: post #85
dangrossman wrote: post #82

Earlier quoted context omitted.

It's really not. If you want a citation for "growing trees takes CO2 out of the atmosphere", a high school bio book will suffice -- the carbon mass of the tree is carbon extracted from the atmosphere (and dead plant mass in soil, but the carbon there came from the atmosphere too). If you want a citation for growing trees for timber and pulp as an effective CO2 sink, the citation is right in the grandfather post (an i…

I was more interested in the source for the specific number you gave. Should have been less snarky, sorry!

The US tree usage statistic originally came from TAPPI (the tree pulp, paper, packaging, and converting industry assocation).

Re: 6 month read-through/discussion of Gödel, Escher, Bach starting 1/17 on Reddit

#87

Post by noahth »

JonnieCache wrote: post #22
brianwillis wrote: post #4

It's such a shame there isn't a Kindle/ePub/PDF version. I guess I'm off to kill another tree.

To anyone looking to purchase themselves some dead trees, I recommend that you pick up an older second hand copy. I have it on good authority that the recent 20th anniversary reprint is of a much lower quality, with crappy thin pages and less clear type.

Possessing both versions, I can confirm that the paper in the anniversary edition is thinner, but I think if anything the type is easier to read. YMMV, of course.
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