I find the overall argument to be rather weak. The most relevant problem is that it starts on a premise that might as well be this: "Intelligence is a substance, and a nootropic is a drug that makes the brain produce more of it."

Of course I've intentionally phrased this as to make it seem ludicrous, but throughout the article he talks of "more" or "less" intelligence as though it were a fungible sort of thing. Really, though, intelligence is just a way that human beings interpret each other's behavior, related to performance on various tasks (mathematics, etc). There's no particular reason to assume that evolution would have optimized for, e.g., skill in mathematical analysis, and therefore there isn't any particular reason to assume that even the silliest of low-hanging fruit wouldn't have been picked, for instance an elderly and distinguished analyst, such as Paul Erdos, may benefit from taking amphetamine.

There are also radical differences in what we measure as "IQ", which is mostly performance on a battery of strange tasks, and the sort of mental performance that leads to evolutionary success. There are, for example, arguments to the evolutionary sufficiency of ADHD[1], OCD[2].

1: http://en.wikipedia.org/wiki/Hunter_vs._farmer_hypothesis

2: http://en.wikipedia.org/wiki/Ocd#Causes

More critically, though, is that this represents yet another article on the basis of "I-think-it-oughta" evolutionary reasoning. You think "intellectual low-hanging fruit" ought to be selected for, but you don't have empirical evidence. The claim is based almost entirely on hand-waving and citations of Eliezer Yudkowsky, who is not in any case an authoritative source [3], and whose claims have not been in general accepted by contemporary neuroscientists [4].

3: http://rationallyspeaking.blogspot.se/2010/09/eliezer-yudkow...

4: notably absent here: en.wikipedia.org/wiki/Evolution_of_human_intelligence and here: http://scholar.google.com/scholar?q=evolution+intelligence+a...

Meanwhile, experimental evidence is contradicted. For instance, amphetamine is correlated with improvements in IQ, not to the tune of 20 points, more like four[5]. In fact, things as random -- and ostensibly detrimental -- as mescaline[6] can improve certain aspects of mental functioning, albeit at the cost of others. That what are essentially shots in the dark can produce noticeable improvements in certain qualities bodes well for rational drug design, which has been a success in other fields e.g. cisplatin vs. imatinib.

5: http://en.wikipedia.org/wiki/Amphetamine#Medical

6: http://www.medpagetoday.com/Psychiatry/Addictions/2070

Another thing that is important to keep in mind is that the workings of the body can be highly counterintuitive. For instance, one might expect choline supplementation to increase the level of brain acetylcholine. It seems natural, right? But it's not true[7]. Furthermore, while piracetam's effects are commonly considered to be affected (and side-effects reduced) by choline supplementation[8], it is now generally believed to act primarily as an allosteric modulator on ion channels linked to AMPA-sensitive glutamate receptors[9]. Facile reasoning of the sort "what negative effects might have prevented evolution from doing this" thus cannot, itself, tell us very much.

7: http://onlinelibrary.wiley.com/doi/10.1002/mrm.1910390619/fu...

8: popular claim on longecity et al, e.g.: http://www.pillscout.com/2013/06/17/your-piracetam-dosage-is... , http://www.bluelight.ru/vb/threads/181563-any-piracetam-user...

9: http://pubs.acs.org/doi/abs/10.1021/jm901905j

The most immediately difficult claim to me is the advocacy of spaced repetition, when it is not clear why the claims of the article necessarily apply to drugs but not to techniques such as this -- could we not evolve to use it instinctively?

For all this, there is a little useful data in the article. It is indeed widely suspected that choline is underrepresented in modern diets[10], possibly because major dietary sources of choline include eggs and fatty meats, which have been discouraged in Western diets due to a now-controversial belief that cholesterol and saturated fats are antinutrients. There are indeed large differences between WEIRD[11] and historical environments, many of which go without mention -- socializing is much easier, our lives demand much less energy, the risk of malnutrition has been all but eliminated, etc.

10: http://en.wikipedia.org/wiki/Choline

11: http://www.facstaff.bucknell.edu/jvt002/BrainMind/Readings/H...

The general thrust of my post is that "evolution" is not an argument that computer scientists can throw around in order to do biology without actually studying it[12], and that evolutionary psychology is often subject to epistemological problems, cf. The Emperor's New Paradigm[13].

12: http://www.amazon.com/Behavioral-Genetics-Robert-Plomin/dp/1...

13: http://commons.lib.niu.edu/bitstream/10843/13182/1/BullerTiC...