Thinking Complete

I've been listening to quite a few podcast episodes lately, particularly Rationally Speaking, the 80000 Hours podcast, EconTalk and Conversations with Tyler (who runs the excellent Marginal Revolution economics blog ). I was very impressed by a Rationally Speaking episode with Dr Herculano-Houzel, a brain researcher (here's my blog post about it ), as well as the 80,000 Hours episode with Anders Sandberg. Anders does a wide range of very creative and original research; here he was talking about hibernating aliens , interstellar warfare , and how quick colonising the universe could be . I'd previously seen these arguments as intellectually fun but fairly irrelevant. But on the podcast, Anders presented them in a new light: not simply as speculations on what aliens might be doing, but also as a way of exploring strategies that humans might want to use in the far future. Now that I think about it, that does seem pretty important. I've finally written some political blog...

This month, I've compiled a list of issues that I've been wrong about. International development. I'm pretty libertarian on domestic issues, and so I automatically assumed the same mindset regarding the international economy: thinking that the "Washington consensus" was a broadly good idea, and that encouraging free trade is the biggest priority. However, I was wrong on that: I underestimated the extent to which Asian growth relied on strong and stable governments, and the extent to which deregulation eroded aspects of African governments necessary for private enterprise. I want to put up a few political blog posts in the next month which explore these ideas further. Moral realism. As a good reductionist, I used to think that moral realism was entirely incoherent. Then I read Parfit on personal identity, and had conversations with a few friends (notably Paul F-R), and realised that insofar as we can identify what is "rational" and "irrational...

Thanks to Tom for pointing me to this presentation by a couple of Oxford philosophers who may just have solved Fermi's Paradox (the puzzle of why we haven't seen any alien civilisations, given that plausible estimates for terms in the Drake equation predict that there should be many thousands in this galaxy alone). The main idea is actually quite simple: that people have generally tried to find plausible expected values for each term, then multiplied them together to give an expected number of alien civilisations in the thousands or millions. But if we instead multiply together a whole probability distribution for each term, we get the same mean but a median less than 10, and a double-digit probability that there are no other alien civilisations (the first couple of slides explain this quite well). Their final best guess, given our observations so far, is that there's something like a 40% chance that we're alone in the universe. While this isn't a particularly d...

My degree has forced me to start learning some linguistics, which turns out to be very interesting. It feels like, in trying to figure out what understanding language really means, we're grappling with the very notion of concepthood, and the nature of intelligence itself. My thesis is based on the question of how to represent words in machine learning models. Vectors seem to work pretty well, and make intuitive sense for nouns and verbs at least. In this model, if you take king, subtract man, and add woman, you get queen. Something can be more or less 'rain' (drizzle, shower, downpour, torrent), or more or less 'run' (jog, lope, sprint), or even more or less 'bird' (ostrich, penguin, vulture, sparrow). Things get a little more complicated when we consider determiners, conjunctions, and prepositions, since you can't really be more or less 'for' or 'or'. And when it comes to putting it all together into representations of sentences, we rea...