Gödel Incompleteness for Startups (2013)
skibinsky.com
skibinsky.com
The essay publication was quite impactful in middle of that insanity. It uses Gödel analogy to demonstrate that no amount of formalization (that helps reduce human/team/org risks) will in any meaningful way reduce the systemic risk of a new startup. It placed Gödel formalism straight on the path of hustler/carpetbaggers who were trying to launch new funds and incubators at that time "well, go ahead and prove to your LPs you have Gödel-like formalism that detects great startups at an early stage and you do it better than YC".
Right now most of the essay conclusions are self-evident, "lean startup" is an insult, so it does seem like the author spending a lot of pages and energy on proving something plain obvious.
That wasn't that clear and that obvious many years ago when it was written.
Wait, what?
The thing is, Godel didn't live in an era of pervasive computing so he came up with a wonky encoding based on products of powers of primes. This makes the proof technically challenging, but the fundamental idea is not that complex. What he was able to eventually do was encode a recursive statement of the form "this statement is not provable" where the "this" is kind of like a pointer back to the full statement. The rest is straightforward.
* axiomatizable extension of Q
* consistent
* complete
(where Q is a minimalistic arithmetical theory that can do addition and multiplication: https://en.wikipedia.org/wiki/Robinson_arithmetic)
It's true that the "main idea" of the proof is "everything is a natural number", which is obvious to us programmers (it possibly wasn't obvious to anyone in Godel's time). However, this is by no means the only trick that's used in the proof.
Is this a dig at Hilbert?
Unfortunately, the [Gödel 1931] proof fails for the claimed Russell's system for the foundations of mathematics.
The following has an explanation of what went wrong in this and many other cases in foundations of mathematics for computer science:
Vanquishing ‘Monsters’ in Foundations of Computer Science: Euclid, Dedekind, Russell, Gödel, Wittgenstein, Church, and Turing didn't get them all ...
https://papers.ssrn.com/abstract=3603021Peter Thiel's analogy of this is "what's true but few people agree with you on" and pg's version is "the best ideas look like jokes / bad on first glance". There's a popular venn diagram that's almost analogous to the one in the article: the best startups are at the intersection of true and not obvious.
This article maps "obvious good ideas" to "provable in a formal system", which makes the Godel analogy work, but the Godel analogy seems like a worse analogy.
Analogies are supposed to put a new concept (startup ideas) in terms of more accessible concept (Godel statements?). The analogy target (Godel statements) was so obtuse that the author needed to spend pages explaining it.
Also, the Godel analogy is misleading. The canonical Godel sentence is self referential and also refers to the formal logic system -- a good startup doesn't need to be self referential or refer to the formal system. Besides generating Godel's incompleteness theorem, I don't think Godel statements are "interesting", unlike the most recent successful startups. (In fact, what's interesting are simple yet difficult theorems that were totally provable within Peano arithmetic to begin with, like Fermat's Last Theorem.)
(As an analogy, in theory there are tons of different ways to construct non-measurable sets, but in practice all examples come down to some quotient of a nonzero measure set and a measure zero set, like [0,1]/Q.)
Also, the ultimate monopolist would not play by the formal rules of the game. He would make the rules so simple, that now he indeed can formally derive all truths and exploit these.
More-or-less this. I'm going to take this as an opportunity to drop one of my favourite quotes, because I can't help it:
"The view that machines cannot give rise to surprises is due, I believe, to a fallacy to which philosophers and mathematicians are particularly subject. This is the assumption that as soon as a fact is presented to a mind all consequences of that fact spring into the mind simultaneously with it. It is a very useful assumption under many circumstances, but one too easily forgets that it is false. A natural consequence of doing so is that one then assumes that there is no virtue in the mere working out of consequences from data and general principles."
-- Alan Turing, Computing Machinery and Intelligence
This one is the most egregious case I've seen though. It seems like it would be a waste of time to read, so I closed out fairly quickly. Have I misjudged the article?
You need a sea of risk takers and tinkerers (entrepreneurs and hobbyists) to bring the best ideas to life.
Ever since Gödel proved his theorem, people have used it as a metaphor for all kinds of things, from new age mysticism to psychology, biology, quantum physics, AI etc.
It's a very worn metaphor and mostly used by people who don't actually understand the theorem precisely, just the imagined "gist", often with fundamental misunderstandings. A bit how people use Eistein's relativity theory to then derive moral relativism because "everything's relative".
This blog post may actually provide insight, but it's too long to see.
Given the prior that Gödel is often used just to borrow the prestige and aura of mathematics and to sell insight porn, I cannot justify reading it without seeing a summary.
I start to appreciate the rigid form of scientific articles more and more. People often say it's too rigid, too contorted, we'd be better if people just wrote blog posts in plain language, but then you get unstructured page after page, where you don't know where to look. With some training one can quickly assess the importance/relevance of scientific articles, exactly due to the rigid format. Here I have no idea where I can find the main idea. It is important to be effective in getting ideas across.
> Ever since Gödel proved his theorem, people have used it as a metaphor for all kinds of things, from new age mysticism to psychology, biology, quantum physics, AI etc.
Including Gödel himself, who was a mystic. It is true that people make all sorts of silly claims vaguely based Gödel and other famous results, but it is also true that there are indeed deep philosophical insight to gain from Gödel's theorems, which are also dismissed without a proper argument.
> I start to appreciate the rigid form of scientific articles more and more.
I always appreciated it, but notice that what Gödel did is not science. He obtained a deep insight about reality that was not based on the scientific method or on empiricism.
I really doubt axioms have even been assigned to this problem.
Roger Penrose's "The Emperor's New Mind" also has some good material on GIT.
It seems to be good start up ideas exist in the 'one step removed' phase space of all possible startups - not so far advanced that you need to teach Henry Ford about computers, but just one extra 'twist'.
This seems to be however leading to startups should iterate through 'Facebook but for [dogs,cats,fish,mobile phones]" which I am not sure wins.
But I loved the history of Godel etc.
Can anybody give me an TL;DR?
I'm glad I didn't waste more time on this article.
https://en.wikipedia.org/wiki/Diagonal_lemma#Proof
This proof consists of just 7 lines, but these 7 lines are considered to be fiendishly unreadable. The lemma itself says otherwise something very understandable and perfectly relatable:
logicSentence <-> prop(%logicSentence)
Meaning of the lemma: If prop(%s) is a predicate property of any logic sentence s, then there exists at least one true sentence for which this property is true and/or one false sentence for which it is false. The expression %logicSentence is the (numerical) description (encoded as a number) of the logicSentence. The remainder of Gödel's proof is just endless bureaucracy to establish completely precisely in/from what type of theory it occurs/can be derived.
If you leave out the bureaucracy, Gödel's first incompleteness theorem follows almost trivially from the lemma:
logicSentence <-> isNotProvable(%logicSentence)
Hence, according to the expression above, there exists at least one false sentence that is not isNotProvable (and is therefore provable) [a] or at least one true sentence that isNotProvable [b]. Hence, the theory in which this situation occurs is inconsistent [a] or incomplete [b].
Now, the bureaucracy in Gödel's full proof actually does matter, because his theorem holds for the Peano and Robinson formalizations of arithmetic theory but not for the Skolem and Presburger ones. The reasons for that can only be found in the bureaucracy of Gödel's proof.
There is no fixed point (Diagonal Lemma) for the mapping Ψ↦~⊢Ψ because the order of the proposition ~⊢Ψ is one greater than the order of the proposition Ψ because Ψ is a propositional variable.
For a correct formal proof that there are true but unprovable propositions in the most powerful foundations see the following:
Physical Indeterminacy in Digital Computation
https://papers.ssrn.com/abstract=3459566