

Stephen Wolfram IAmA On Reddit (3pm EST) - nswanberg
http://www.reddit.com/r/IAmA/comments/tmutz/stephen_wolfram_nks_10th_anniversary/

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minimax
Anyone interested in NKS might also be interested in Cosma Shalizi's review
which details several substantial problems with the book.

<http://www.cscs.umich.edu/~crshalizi/reviews/wolfram/>

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taliesinb
It might be good reading, but I don't think its a good review. What follows is
my review of the review, which is rather long, but I've been meaning to write
something for a while, so here it is.

The review is filled with a lot of Shalizi saying how bad Wolfram's book is,
but when it comes time to justify his criticism he seems either to get bogged
down in something quite orthogonal to what Wolfram is actually saying, or to
recap some history without relating it to his original claim.

I feel like a good-faith review should at least try to understand what the
original author's major claims are, state them, and then weigh them. He hasn't
done this. In fact, I suspect he hasn't read very much of the book at all. Of
course, he doesn't have to, but then he must refrain on passing judgement on
the core ideas, especially when the core ideas aren't actually intelligible to
him.

Here's a list of concrete criticisms from Shalizi's diatribe that I was able
to identify. I follow each with my own thoughts, as someone with mathematical
training who has both read the book and been to the summer school
(<http://www.wolframscience.com/summerschool/>).

0) "Wolfram's main discovery and idea is that "simple rules can produce
complex results", something that is neither novel nor helpful."

Actually, Wolfram's discovery is that the very _simplest_ non-trivial programs
that incorporates time and space can be arbitrarily complex (loosely
translated, 'universal'). Furthermore, after doing exhaustive enumerations of
many program families, it is demonstrated that _most_ of them have this
property.

Those qualifiers make a difference; because now Wolfram is studying the
zoology of programs, instead of the piecemeal taxidermy that was attempted
before.

1) "Wolfram's chapter on perception recycles the production rules approach to
cognition."

This is a bizarre conclusion. It seems to be taken from about two sentences
out of a chapter of around 90 pages. Actually, to the extent that Wolfram
offers a theory of cognition, it is closer to Jeff Hawkin's hierarchical
temporal memory.

Now, there are several interesting claims and ideas (perhaps wrong) in the
section on perception, but Shalizi doesn't have anything substantive to say
about them, for them, or against them.

2) "Wolfram doesn't understand evolution. Also, programs can't explain
evolutionary adaptation."

The first claim is unlikely.

The second claim is true, but once again Shalizi seems to have misread (or not
read) Wolfram. Wolfram doesn't claim that programs are responsible for
evolution, but rather than lots of complexity comes 'for free' without natural
selection having to incrementally produce it. Natural selection can preserve
these useful programs once they have been discovered, but they cannot be
constructed piecemeal.

3) "Wolfram is dabbling in toy computer models, nothing more."

It's easy to perceive it that way. I think this is just a side effect of how
wide open the space of programs is. It is an orchard so large, with so many
low-hanging fruit, that the logical thing _isn't_ to construct one extremely
good snowflake model and write a book about it, but to show that even an
absurdly simple one can get you further than most numerical models do, and
then go on to show the same thing for a dozen other problems.

No particular example is meant to be both novel and definitive. Rather, the
whole collection of examples is to demonstrate that a connecting thread of
extremely simple programs runs through very many scientifically and
mathematically interesting questions, and that a small amount of tugging on
each one can yield some disproportionately impressive answers -- even if the
models are overly simplistic.

4) "Wolfram fails to define complexity other than visually."

Shalizi misses the point about metrics of complexity, thinking that the lack
of a single definition of complexity is a bad thing. Instead, it represents a
new approach. Let me explain in more detail.

The basic premise is that any particular (practical) complexity measure boils
down to using a particular program to shortcut or predict the evolution of a
process. Wolfram argues this is both true of hardcore statistical analysis and
"folk analysis", i.e., looking at stuff visually.

Recall that Wolfram claims that most non-trivial processes are "irreducible":
you have to run them to find out what they do. Therefore, definitionally, they
cannot be shortcut by any practical complexity measure. That means that most
complexity measures will agree on all the interesting cases: they'll all
'break a tooth' on the nugget of irreducibility and claim them to be maximally
complex.

So _if_ the principle of computational irreducibility is true, _then_ we have
the conclusion that devising complexity measures (while a fun game to play) is
not actually that crucial to whole enterprise of understanding complexity.

5) "Wolfram doesn't understand relativity and/or Bell's inequalities."

I don't know any loop quantum gravity, so I can't comment on how much deeper
it is than Wolfram's work on trivalent nets.

Actually, Aaronson's claimed disproof of the network universe really hinges on
whether you allow weak, long-range connections in the graph. It's more of a
stalemate.

6) "Wolfram tried to use Cook's result with crediting him."

There is no evidence for this claim -- from what I've heard, Cook broke an NDA
he signed that required him to wait for the publication of the book to talk
about the result, and then broke _another_ agreement by trying to publish it.
But ultimately, it's a "he said, she said kind of thing" -- we cannot conclude
anything about the character of either of them.

7) "Wolfram gets the history wrong."

No examples of actual errors are provided, although "indefinite examples are
available on request". 'Indefinite' is a good choice of word.

8) "Wolfram's style is unpleasant."

I happen to think that most of it is written in simple, straightforward,
unpretentious language -- contrary to much academic work. Of course, this
isn't an academic work, and wasn't purporting to be written in academic style.

From history, we have two diametrically opposed examples of style for large
scale scientific works: Newton's Principia, which was so technical, dry, and
austere that it took quite a long time for people to actually start reading it
and absorbing the ideas; and Darwin's Origin of Species, which was
straightforward, readable, and sold out on the first day.

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minimax
So Wolfram thinks he is the Charles Darwin of what exactly? The Origin of
Species has a singular focus, i.e. presenting evidence for the mutability of
species. What is NKS's focus? What makes you think NKS is in any way
comparable to Origin of Species?

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taliesinb
Read my sentence carefully. The only point of comparison is that they are both
"large scale scientific works".

But since you asked, NKS's focus is simple programs.

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dude_abides
This was his reply to a question asking him to have a bug bounty program like
Knuth.

 _We could have bankrupted Don Knuth when we first started automatically
generating TeX from Mathematica years ago!_

Talk about humility..

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taliesinb
You seem not to be aware that he's joking.

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skeletonjelly
Sarcasm is hard to portray in text. He's clearly really good at it.

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Skyhook-
Stephen Wolfram's AMA from March 5, 2012.

[http://reddit.com/r/IAmA/comments/qisot/im_stephen_wolfram_m...](http://reddit.com/r/IAmA/comments/qisot/im_stephen_wolfram_mathematica_nks_wolframalpha/)

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hexagonal
So he's doing an AMA every two months?

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doug1001
Question to SW about this favorite books:

 _On my desk I have to say I have only one book: A New Kind of Science._ [by
Stephen Wolfram] _But within reach, I have [N]ewton, Darwin, Euclid, Galileo,
Boole, D'Arcy Thompson, Linnaeus."_

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koglerjs
what, did he want more attention?

I have a hard time giving his work the respect it admittedly deserves because
of the weight of his ego.

