This book is about the globalization triggered by Columbus. The book’s jacket describes this set of changes as “the most momentous biological event since the death of the dinosaurs”. But that was probably written by a poorly informed marketing person. The contents of the book promote a more plausible claim that the effects were bigger than most realize.

Some of the ideas that this book reports are surprising, potentially important, but also somewhat speculative. E.g. large-scale reforestation resulting from smallpox killing existing inhabitants apparently contributed to the little ice age by sequestering carbon.

Much of the book is devoted to the spread of non-human species, but there are long sections on slavery, including speculation about how cheap land might have made slavery more important, and how the differences between Algonkian and Mississippian Indian cultures may have affected attitudes toward slavery in northern and southern U.S.

The first quarter of the book seemed well written, but the remainder of the book wanders through anecdotes of unclear importance. If I’m trying to focus on long-term effects of the globalization that Columbus triggered, why should I care about the details of numerous battles?

The book might come closer to living up to the jacket’s hype if it argued that Columbus caused the industrial revolution. But Mann seems confused about what the industrial revolution was – he treats rubber as a necessary component of the industrial revolution, but that happened well after experts say the industrial revolution started.

It wouldn’t be hard to use the ideas in this book to generate speculation that Columbus caused the industrial revolution, e.g. the potato’s ability to feed several times as many people as wheat, as well as cheaper security due the difficulty of stealing potatoes which are left in the ground until needed, made more people available to invent technology, and might have generated wealth and predictability that enabled inventors to focus on more distant rewards. But my guess is that this is only a small part of what caused the industrial revolution.

This book is an excellent introduction to the heuristics and biases literature, but only small parts of it will seem new to those who are familiar with the subject.

While the book mostly focuses on conditions where slow, logical thinking can do better than fast, intuitive thinking, I find it impressive that he was careful to consider the views of those who advocate intuitive thinking, and that he collaborated with a leading advocate of intuition to resolve many of their apparent disagreements (mainly by clarifying when each kind of thinking is likely to work well).

His style shows that he has applied some of the lessons of the research in his field to his own writing, such as by giving clear examples. (”Subjects’ unwillingness to deduce the particular from the general was matched only by their willingness to infer the general from the particular”).

He sounds mildly overconfident (and believes mild overconfidence can be ok), but occasionally provides examples of his own irrationality.

He has good advice for investors (e.g. reduce loss aversion via “broad framing” – think of a single loss as part of a large class of results that are on average profitable), and appropriate disdain for investment advisers. But he goes overboard when he treats the stock market as unpredictable. The stock market has some real regularities that could be exploited. Most investors fail to find them because they see many more regularities than are real, are overconfident about their ability to distinguish the real ones, and because it’s hard to distinguish valuable feedback (which often takes many years to get) from misleading feedback.

I wish I could find equally good book for overuse of logical analysis when I want the speed of intuition (e.g. “analysis paralysis”).

This book contains a fair amount of interesting information, but the writing style leaves much to be desired, and many parts disappointed me.

It describes savant syndrome (formerly known as “idiot savant”), where unusually good numeric or artistic skills coexist with some sort of mental disability (and usually prodigious memory).

Some people appear to have been born with savant skills, a few developed the skills in what appears to be a sudden insight. But the cases that seem to tell us the most about what is special about savants are the ones where the skills emerge after a brain injury. Savant skill seem to be often caused by a left brain dysfunction removing some inhibitions that prevented the right side of the brain from developing or displaying unusual skills.

This suggests that there may be some sense in which we all can potentially develop savant skills.

He doesn’t provide a good explanation of why the syndrome is defined so that savants with no disability fail to qualify. There seems to be some tendency for savant skills to coexist with some drawbacks (such as the drawbacks associated with autism), but the author denies that there’s any trade-off requiring that savant skill cause deficiencies in other areas.

Some of the weaker parts of the book claim some savants know things they couldn’t have learned, and attribute skills to genetic memory. I find it much more plausible that the savants learned their skills in ways that would look like an extreme form of normal learning, and that we just don’t know how to observe when and where they accomplished the learning.

It’s very popular in India, but hasn’t gotten as much attention in the U.S. as it deserves.

The early parts of the movie remind me of the better parts of Ferris Bueller and MacGyver (including some of the ethically questionable parts of Ferris Bueller). The last half is more serious, more impressive, and harder to describe. I was surprised at how quickly it could alternate between making me laugh and making me sad.

It’s longer than I normally want a movie to be, but there are hardly any parts that I would have wanted cut. I want to thank the Netflix recommendation system, without which I probably wouldn’t have heard of it.

The reaction of Hypothalamic orexin/hypocretin neurons to amino acids (especially nonessential amino acids) appears to be a mechanism for this effect.

Poultry products appear to be one of the better ways to get nonessential amino acids.

I’ve been trying to increase the protein in my diet for the past four months (in response to weaker evidence than I’ve linked to here), and have found that animal sources have been the easiest way to do that (I’ve mainly increased my egg and meat consumption). I think I’ve found it slightly easier to avoid gaining weight. I think I’ve also been more alert, but I don’t think the increase in alertness coincided too closely with the increase in protein consumption.

Pinker provides a cautiously optimistic view of the dramatic reduction in violence over the past few centuries. He has tied together a wide variety of violent behavior (from genocide to cruelty to animals) into one broad pattern of people becoming more civilized.

He mostly covers the west, and I wished for more about the trends in the mideast and the more peaceful parts of asia. And why does he avoid commenting on the reported homicide rate for Somalia that’s less than the US – does he have reject the data as inaccurate, or does he want to ignore evidence that’s inconsistent with his claim that the rise of leviathan reduced crime?

The substance of the book is less reassuring than a casual glance would suggest. In particular, the section on the power law distribution of war deaths shows that the model he uses says the expected number of war deaths is infinite, apparently due to small probabilities of really destructive wars. It’s easy to overlook this disturbing implication if you aren’t reading carefully. I’m disappointed that Pinker didn’t talk about this more – how is it altered if we try to incorporate the finiteness of the available population? Should we focus a lot of our attention on avoiding unlikely megawars?

He cautiously speculates about possible causes (increased global communications, trade, democracy, self-control, reason, feminization, education, and intelligence via the Flynn effect).

If you’re an ideologue looking for an excuse to be offended, you’re fairly sure to find one in this book.

Pinker exaggerates the evidence for violence among hunter-gatherers (see the book Sex at Dawn for the other side of this debate). And the evidence Pinker does present is quite consistent with the hypothesis that violence increased when people switched from hunter-gatherers to stationary farmers.

The book is very long, and that’s not due to a simple desire to be thorough. Much of the evidence seems selected more for vividness and memorability (e.g. his evidence from fairy tales – not completely frivolous, but insignificant enough evidence that he wouldn’t have put it in a peer-reviewed article).

I didn’t learn enough from it to justify the time spent, but the ideas in it deserve to be known more widely.

This book contains a few good ideas, expressed simply and clearly. It explains some of what caused the 2008 financial crisis. But he exaggerates a good deal when he claims he has “provided empirical proof that monetary policy was a key cause of the boom”.

He provides clear evidence that counterparty risk was a more important problem than lack of liquidity, and has some hints about how counterparty risk could have been handled better. But that doesn’t say much about whether policies to deal with liquidity problems were mistaken – I doubt that many of the people pushing those liquidity related policies were denying that counterparty risk was a problem.

I’ve been convinced since before the crisis that having the Fed follow the Taylor Rule would have been better than the monetary policy that we actually had. But the details of the rule seem somewhat arbitrary, and I’m disappointed that the book doesn’t provide much explanation of why the Taylor Rule is better than alternative rules.

I’ve found a link on Taylor’s blog to an article (The Taylor Rule and QE2 By David Papell) which compares it to some alternatives which seem motivated primarily by a desire to rationalize more monetary or fiscal stimulus. But what I want to know is whether it’s possible to create a rule that is more countercyclical without being more inflationary.

I have an intuition that it’s not too hard to improve on the inflation component of the rule. The CPI seems to have many drawbacks, such as being slow to reflect changes. I suspect Taylor’s inflation coefficient of 1.5 is larger than what an ideal rule would use in order to make up for the delays associated with using the CPI. When I’m estimating inflation for my investment decisions, I pay more attention to the ISM price index, the money supply (MZM), commodity prices, and stock prices. And the ISM Purchasing Managers Index should provide more up to date evidence of the “output gap” than GDP figures. A version of the Taylor Rule which emphasized those should react more quickly to changes in the economy.

the demand for Bitcoins is driven by the volume of Bitcoin-denominated transactions.

…

the value of a currency is built on its reputation, and five months of bad news and depreciation have done serious damage.

Money serves several different functions. To be widely accepted, a currency typically needs to serve as a medium of exchange and as a store of value. But gold is a good example of a quasi-currency that functions as a fairly good store of value (at least for people with long time horizons). Bitcoin shows more promise of functioning as a store of value than as a medium of exchange.

If Bitcoin were only a medium of exchange, it might make sense to say the volume of Bitcoin transactions drives the demand for it. But if most people who are buying Bitcoins are hiding them under their mattresses on EMP-resistant media (cd-rom?), the price of Bitcoins can rise indefinitely without an increase in transactions.

It isn’t very useful to lump many beliefs about a currency into a single reputation. Bitcoin has different reputations for different traits.

A currency should have a reputation for being in limited supply and for not having that supply increase too rapidly. I’d say Bitcoin has developed a better reputation for this than the US dollar, and might exceed gold’s reputation.

A currency should be easy to store and transport safely. This is an area where Bitcoin’s reputation is the subject of much confusion. There’s currently an unpleasant tradeoff between secure ways to store Bitcoin and convenient ways to have them available to spend. It make take a major rewrite of operating systems (e.g. to use Capability-based security with a good UI) for it to be possible to have Bitcoins be conveniently accessible but hard to steal. Confusion over the risk of theft has probably driven a fair amount of the recent Bitcoin price volatility. My guess is that it’s better that theft has happened now than after people become more reliant on Bitcoin. It will either drive the creation of more secure software (with benefits much wider than Bitcoin use) or discourage people from relying on insecure ways of handling digital money.

Finally, it’s important that a currency have a reputation for being something that people will value in the future. This is a source of significant uncertainty, because it depends on people’s perceptions of the alternative stores of value, the alternative media of exchange, and the risk of Bitcoin theft. Bitcoin has the potential to be a better store of value than gold, because a transparent algorithm can better guarantee a limited supply than the difficulty of mining a metal. People who started watching Bitcoin prices a few months ago in response to a flurry of publicity attach a low reputation to its prospects as a store of value because the recent price crash is more vivid in their mind than the earlier boom, but that’s a temporary phenomenon that doesn’t deserve much attention.

For most uses as a medium of exchange, Bitcoin doesn’t offer much advantage now. For most transactions, the small cost savings aren’t enough to persuade consumers to give up the ability to dispute a payment, or for stores that accept Bitcoin with an option to dispute payment to offer a discount for Bitcoin purchases. And I expect governments and large financial institutions to create obstacles to its use as a medium of exchange. There are a few small uses where it works better than any existing alternative – e.g. Wikileaks, where the existing financial system refuses to support online payments. Bitcoin anonymity doesn’t appear strong enough to attract people engaged in illegal businesses. Online gambling companies might get some advantage from using Bitcoin if the obstacles to transferring money to gambling sites exceed the obstacles to buying Bitcoin, but I’m guessing the obstacles are and will be at least as large for buying Bitcoin. So I expect very slow adoption of Bitcoin as a medium of exchange.

I do think there’s a nontrivial chance that Bitcoin will become widely used as a store of value, and that might replace a significant amount of demand for gold a decade or two from now. A decline in demand for gold as a store of value might well snowball, as extrapolating that trend would imply that gold becomes a less reliable store of value. That doesn’t yet make me reluctant to buy gold, but a Bitcoin price over 0.1 ounces of gold might make me reconsider.

I will probably invest a small fraction of my net worth in Bitcoin, but I don’t feel any urgency about it.

It has been reported to be addictive, but I haven’t felt that it’s any more addictive than chocolate. One important caveat is that if I use it two days in a row, the effects are dramatically reduced on the second day. That’s probably what leads to addiction – people are tempted to use it every day, which creates a temptation to use much larger quantities. I’ve been restricting my use to once or twice a week, and I’ll try not to increase that frequency.