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[–]its4thecatlol 2 points3 points  (10 children)

This is an example of where evolutionary biology is just taken to its logical extreme past the point of absurd. Just because something hasn't happened yet doesn't mean it can't. Here's a question: If some people have genes that increase intelligence, why don't we all have them? The evolutionary extremist would say it's because the same gene might negatively effect other systems, but this is a bad oversimplified heuristic that needs something more than speculation.

Most of human evolution was done running through jungles and whatnot, and intelligence would not be particularly favored past the basics. Being super-smart wouldn't help you much more than being slightly smart when it comes to chasing animals or running from them.

[–]gwerngwern.net 3 points4 points  (6 children)

Here's a question: If some people have genes that increase intelligence, why don't we all have them? The evolutionary extremist would say it's because the same gene might negatively effect other systems, but this is a bad oversimplified heuristic that needs something more than speculation.

Already covered in my essay; in fact, far from being 'past the point of absurd', you came up with literally the perfect demonstration of Algernon's law - see the horrifying genetic disorders in the Ashkenazi combined with a remarkably high average IQ...

Most of human evolution was done running through jungles and whatnot, and intelligence would not be particularly favored past the basics. Being super-smart wouldn't help you much more than being slightly smart when it comes to chasing animals or running from them.

Already covered in the essay; and not true, more smarts are always better since they help in social games, help in spatial navigation and planning, and intelligence & simple reaction-time are closely linked.

[–]its4thecatlol 1 point2 points  (5 children)

horrifying genetic disorders in the Ashkenazi combined with a remarkably high average IQ

The genes for the two are different. Not only that, but the genetic disorders are very rare compared to the prevalence of high-IQ individuals. Terrible example. Even if the two were caused by the exact same gene (which I repeat they are not), Algernon's "Law" is still violated - jewry is indisputably better off. Jews have a reputation for being rich and smart, not for toy-sachs disease.

Already covered in the essay; and not true, more smarts are always better since they help in social games, help in spatial navigation and planning, and intelligence & simple reaction-time are closely linked.

Even today, IQ over 125 doesn't correlate too highly with income. That's today, and you think being 160 instead of 125 would make a difference 200,000 - 2 million years ago? Very unlikely.

help in spatial navigation and planning

Not really. Any deficiency from being 125 instead of 160 (just a hypothetical example I'll re-use) is easily going to be made up for by the collective intelligence of the tribe.

simple reaction-time

Not too important honestly. It's not usually a split-second decision, it's your physical fitness that matters in the wild.

[–]gwerngwern.net 1 point2 points  (4 children)

The genes for the two are different. Not only that, but the genetic disorders are very rare compared to the prevalence of high-IQ individuals.

Citation needed. And we're talking about heterozygote advantage, where the disorder is going to be rare compared to the number of carriers - and ever more rare as the concerned populations universally use genetic counseling and testing and abortions to deal with things like torsion dystonia.

Even today, IQ over 125 doesn't correlate too highly with income.

Wrong. Check out the lifetime incomes for the Termites, or look at the more recent results for SMPY kids, and reflect that these are vast underestimates due to the smarter opting for academia and research - they could make ever more money, they just choose not too.

Any deficiency from being 125 instead of 160 (just a hypothetical example I'll re-use) is easily going to be made up for by the collective intelligence of the tribe.

The tribe isn't going hunting.

It's not usually a split-second decision, it's your physical fitness that matters in the wild.

Reaction time matters a hella lot when you're throwing spears or shooting arrows at a moving target. And it gets even worse when we're talking about more primitive tools like throwing stones: "Precise neuromotor control of finger muscles permits submillisecond release times needed for throwing accuracy." (emphasis added).

[–]its4thecatlol 1 point2 points  (3 children)

Citation needed

Are you being pretentious? You can google this, but more importantly you're the one asserting a relationship so it's up to you to prove a causal relationship and not me to disprove it.

1 in 3500 AshJews has TS. They're also not the only ones with it. Cajuns and Quebecois also suffer from a high frequency of the disease. They don't have 125 avg IQs. Your claim that it's somehow related to intelligence is baseless speculation, and plain wrong. Again, the genetic variations for TS are known and they are not the same variations that correlate to intelligence.

Check out the lifetime incomes for the Termites, or look at the more recent results for SMPY kids, and reflect that these are vast underestimates due to the smarter opting for academia and research - they could make ever more money, they just choose not too.

Or we could just look at the studies done on this:

http://thesocietypages.org/socimages/2008/02/06/correlations-of-iq-with-income-and-wealth/

http://researchnews.osu.edu/archive/intlwlth.htm

http://pubs.aeaweb.org/doi/pdfplus/10.1257/089533002760278686

The tribe isn't going hunting.

That is actually what they did. Back in the days of wooly mammoths, it took a lot of guys to take down a single one of them. Maybe the women, children, and elderly stayed behind.

Reaction time matters a hella lot when you're throwing spears or shooting arrows at a moving target.

It matters a lot less when there's 8 people doing the same thing, and you practice at it every day.

[–]gwerngwern.net 2 points3 points  (2 children)

1 in 3500 AshJews has TS. They're also not the only ones with it. Cajuns and Quebecois also suffer from a high frequency of the disease. They don't have 125 avg IQs. Your claim that it's somehow related to intelligence is baseless speculation, and plain wrong.

I haven't see any demonstrations that there is no correlation or advantage.

http://thesocietypages.org/socimages/2008/02/06/correlations-of-iq-with-income-and-wealth/

Lame. You were basing your claim just on Zagorsky? I've already read it when it came out, so I know why that paper is irrelevant; but here, I've even jailbroken a copy so you can read Zagorsky's paper yourself and verify what I say below: http://dl.dropboxusercontent.com/u/182368464/2007-zagorsky.pdf

He doesn't show no or inverse relation, he shows exactly what you would expect - median net worth & income increases monotonically with each IQ bracket! Look at the summary table 2 on pg7. On top of that, his sample is ceiling-limited to ~125, and so largely irrelevant to the Termites and SMPY which were either above that or way above that, respectively.

The quadratic thing is interesting, but emphasizes the point: the average ceiling group is so much wealthier and has such a higher income that it's still wealthier even despite more bankruptcies or whatever.

(Zagorsky also doesn't seem to understand regression: if the increase in wealth is mediated solely through education, then it's absurd to say IQ has no causal effect because you can drop its coefficient to near-zero by regressing on education! Classic over controlling.)

http://researchnews.osu.edu/archive/intlwlth.htm

Dupe of first link.

http://pubs.aeaweb.org/doi/pdfplus/10.1257/089533002760278686

Fail to see its relevance. It neither shows an inverse relationship (shows a positive one, both on its own and mediated via education), nor does it show anything about a cutoff around IQ 125.

It matters a lot less when there's 8 people doing the same thing, and you practice at it every day.

8 people don't get you submillisecond releases based on reflexes. As Brooks quipped in a different context, "the bearing of a child takes 9 months, no matter how many women are assigned to the task."

Back in the days of wooly mammoths, it took a lot of guys to take down a single one of them. Maybe the women, children, and elderly stayed behind.

So, most of the tribe wasn't going hunting, even in your idiosyncratic little hypothetical.

[–]its4thecatlol 0 points1 point  (1 child)

I haven't see any demonstrations that there is no correlation or advantage.

To what? TS disease? You want a demonstration that there is no advantage to it?

He doesn't show no or inverse relation, he shows exactly what you would expect - median net worth & income increases monotonically with each IQ bracket!

You miss the point completely.

Fail to see its relevance. It neither shows an inverse relationship (shows a positive one, both on its own and mediated via education), nor does it show anything about a cutoff around IQ 125.

Where does anyone say there's an inverse relationship? The point is intelligence as measured by IQ is only one of many different factors determining success, and not the most important. It predicts what level of profession you can make it to, but after that it doesn't matter more than many other factors. A lot of it seems to be intangible and hastily labelled 'emotional intelligence.'

8 people don't get you submillisecond releases based on reflexes.

So what? Who cares? The point isn't to have quick reflexes but to be successful hunters. The former can help get to the latter, but it's not a necessity. A group of slow-medium pace hunters could take down a large animal.

So, most of the tribe wasn't going hunting, even in your idiosyncratic little hypothetical.

Further reducing the evolutionary pressures for intelligence.

At this point, you're just arguing minutiae that's not even relevant.

[–]gwerngwern.net 2 points3 points  (0 children)

To what? TS disease? You want a demonstration that there is no advantage to it?

Sure, that'd be helpful. Correlate against sequencing or something, perfectly doable.

You miss the point completely.

I'm glad you benefited so much from my detailed discussion of Zagorsky and the paper I jailbroke for you so you could actually read it. It really warms my heart and demonstrates the value of technical discussions on Reddit.

Where does anyone say there's an inverse relationship? The point is intelligence as measured by IQ is only one of many different factors determining success, and not the most important...It predicts what level of profession you can make it to, but after that it doesn't matter more than many other factors.

Missing the point. As long as it contributes to success, it helps. By definition. And then there's probably going to be selection pressure. If there is no correlation or an inverse relationship, that is what needs to be shown to defeat the claim, and you have not, and your chosen reference shows the opposite, a positive relationship.

The point isn't to have quick reflexes but to be successful hunters. The former can help get to the latter, but it's not a necessity. A group of slow-medium pace hunters could take down a large animal.

As long as it contributes to hunting success, there is selection pressure.

Further reducing the evolutionary pressures for intelligence.

And then we can bring in all the other uses of intelligence, from performance in other jobs to the Machiavellian social intelligence hypothesis to costly signaling...

[–]api -3 points-2 points  (1 child)

This analysis also assumes that evolution is optimizing for intelligence, when in reality it's optimizing for fitness in the Darwinian sense. Intelligence may contribute to fitness (if it didn't we wouldn't be here), but it is not the only contributor and it may have little value beyond some minimal threshold. In some cases high intelligence may be associated with increased risk of mental illness, a fitness penalty.

[–]gwerngwern.net 1 point2 points  (0 children)

This analysis also assumes that evolution is optimizing for intelligence, when in reality it's optimizing for fitness in the Darwinian sense.

No, I did not, and that was a major point! Holy crap, how did you read my essay and get that out of it? The main point was that reproductive fitness is going to be one of the limits, and I even laid out bulleted loopholes and discussed them individually with examples like birth control of how there can be easy convenient free lunches - with the cost of reproductive fitness!

In some cases high intelligence may be associated with increased risk of mental illness, a fitness penalty.

Yes, that's a potential example of the tradeoff, but I've read things which go both ways on the relationship of IQ with mental illness so I haven't included it.

[–][deleted]  (5 children)

[deleted]

    [–]its4thecatlol 1 point2 points  (3 children)

    I think it's just a mental exercise. Even if you don't support it, you have to acknowledge there's some kind of merit to his argument.

    [–]api 1 point2 points  (0 children)

    I think there is merit to the "strong form" of his argument -- there are not likely to be any simple hacks that can yield large improvements in intelligence, especially improvements beyond the boundaries of where evolution's already been. We are extremely unlikely to ever discover a nootropic like the compound in the film "Limitless."

    But I don't think the weak form holds up. There are likely to be any number of hacks that can optimize intelligence in an individual, and their use together might cumulatively achieve some vicinity of the maximum intelligence evolution has achieved in an individual's gene pool. We already know what some of them are, as correcting nutritional deficiencies has shown an ability to boost the IQ of populations.

    Since non-trivial evolutionary fitness landscapes are intractable, there is no way to know how many there might be. The only thing to do is look for them.

    [–]gwerngwern.net 0 points1 point  (1 child)

    It's not 'just' a mental exercise. As api points out, just accepting the 'strong form' may, for a lot of people here on /r/Nootropics, be extremely educational and bring their expectations down to earth.

    Once you've been brought down to earth and have more realistic expectations for supplements or nootropics, then it becomes part of the toolkit for evaluating claims, like being skeptical of animal experiments or human experiments where n=10 (rather than 300) eg. one can ask, "Are they claiming large benefits? No side-effects like weight loss? That it's a simple and easily understood change like 'just have more choline'?" If they are, then their claims are probably too good to be true.

    [–]its4thecatlol 0 points1 point  (0 children)

    FTR you're confusing strong form and weak form.

    [–]gwerngwern.net 0 points1 point  (0 children)

    I'd like to know your reasoning in lieu of the fact they are likely to provide minimal gains.

    I don't take as much as you might think, and what I do take generally does satisfy one of the identified loopholes:

    • I take vitamin D because there's a clear difference between my ancestor's environment of even a century or two ago and how much sunlight I actually get now, and vitamin D has benefits in plenty of human RCTs & meta-analyses
    • I take melatonin to help me sleep because of a very similar environmental difference (blue-colored electrical lighting at night, which did not and could not exist more than ~130 years ago)
    • I sometimes take modafinil because it seems to escape via the fitness loophole by increasing caloric consumption (eg. the side-effect of 'weight loss') and its stimulant properties are well-verified in human RCTs
    • nicotine by similar reasoning
    • creatine because it's so cheap that I'm willing to risk the likelihood of it being useless
    • piracetam+choline: I'm not really sure about this one, but the effects are small and it may escape by the loophole of not being big

    [–]SyncoBeat 2 points3 points  (19 children)

    The assumption that if potentially advantageous modifications existed, then they would already have been found by evolution, is hopelessly wrong.

    The reason is simple, but not 100% obvious. It's that if you have strings that evolve via mutation and selection, like genomes and protein sequences, then this process may be considered to be a search where each possible sequence is assigned a fitness, and selection checks all neighboring sequences (say, that differ in precisely one locus) and moves to the neighboring sequence which has the highest fitness. Eventually you expect to reach the fittest sequence, right?

    Wrong! The landscape will always be multipeaked, and in general the global optimum will not be accessible from all starting points. The genomes get trapped on local maxima which are less fit that the global max.

    The reason the landscape is multipeaked is because of sign epistasis between the loci (positions on the string). Epistasis has lots of biological meanings, but here it simply means that mutations at one site have different fitness values depending on the values of the other sites. Sign epistasis is where a mutation at some site is beneficial on one background but deleterious on another. There is a theorem saying a landscape will be multi peaked iff sign epistasis is present in the landscape.

    And in reality, for biological evolution, sign epistasis is everywhere, obviously, so in general there's absoluly no reason to expect evolution to have found the best configuration of some sequence in the genome, no matter how you define fitness. There's every reason to expect the exact opposite. So Algernon's law is complete BS, for the same reasons Gwern uses to try to argue in it's favor, namely, the existence of tradeoffs.

    This line by Yudkowsky is possibly the dumbest thing ever written about evolution:

    …one reason to be wary of, say, cholinergic memory enhancers [such as piracetam]: if they have no downsides, why doesn’t the brain produce more acetylcholine already? Maybe you’re using up a limited memory capacity, or forgetting something else…

    [–]gwerngwern.net 4 points5 points  (18 children)

    Wrong! The landscape will always be multipeaked, and in general the global optimum will not be accessible from all starting points. The genomes get trapped on local maxima which are less fit that the global max.

    And there is no reason to expect the 'global optimum' to be reached by simple interventions.

    And in reality, for biological evolution, sign epistasis is everywhere, obviously, so in general there's absoluly no reason to expect evolution to have found the best configuration of some sequence in the genome, no matter how you define fitness. There's every reason to expect the exact opposite.

    Even as defined, Algernon's law doesn't claim evolution has reached a global optima for intelligence, and specifically lays out what interventions which can reach a higher local optimum or the global optimum must look like!

    Did you actually read the link or did you just read a few lines and go 'hurr hurr how idiotic!' and smugly post a comment?

    This line by Yudkowsky is possibly the dumbest thing ever written about evolution:

    …one reason to be wary of, say, cholinergic memory enhancers [such as piracetam]: if they have no downsides, why doesn’t the brain produce more acetylcholine already? Maybe you’re using up a limited memory capacity, or forgetting something else…

    And yet, despite it being the 'dumbest thing ever written', you still have not explained why, if they're such great ideas, the brain doesn't simply produce less acetylcholinesterase or something eminently doable with trivial tweaks to something in the cholingeric pathways.

    [–]SyncoBeat 1 point2 points  (7 children)

    Less acetylcholinesterase can be a great idea without being selectively accessible. That's the entire point of my post.

    The same warnings about the difficulty of optimization can apply to drug design too, of course, which your article correctly points out. But the landscape for humans is different, because we can find the peaks through a much more expansive search then nearest-neighbors.

    If you could show me some solid evidence that not only is less acetylcholinesterase easy to do biochemically, which I don't doubt, but that the relevant mutations decrease fitness by epistasis in a way that is also triggered by delivering some drug, then it would be safe to conclude that the drug isn't helping you out. But only then. Because otherwise the drug could well be "easily" increasing fitness in a way that escapes the sign epistasis at the site of the mutation.

    Example: A genome with three sites, and two alleles at each site, a and A at the first site, b, B at the second, c and C at the third.

    Drug design goal: Maximize molecule X.

    The third site has these functions:

    c - weak AND gate for a and b, which upregulates X. C - strong AND gate for A and B, which upregulates X (better than c).

    You will easily see that if abc is the wild type, point mutations will not get you to ABC, which is better, and it has nothing to do with whether delivering X "really is" better or worse for you.

    [–]gwerngwern.net 1 point2 points  (4 children)

    Example: A genome with three sites, and two alleles at each site, a and A at the first site, b, B at the second, c and C at the third.

    You've constructed a fragile toy example, and one which proves too much: if systems were that carefully constructed, how could any assemblage of point mutations over millions of years have built up the incredible diversity and capable systems we see all around us?

    Answer: real biological systems are far more complicated and have far more components, more complicated pathways, interact with other pathways, additional genes can be added in, and there is a combinatorial explosion of possibilities which can be sampled to get a useful effect. Only one possibility needs to work. The more power is added to the system, the less likely it will wind up exactly ruling out all improvements like your constructed example. To analogize: sometimes people think that Turing-complete programming languages must be hard to design and fragile, and the Turing-completeness easy to break; but actually, TCness pops up everywhere and it's remarkably difficult to design a language which does something while not being Turing-complete, to the point where it routinely pops up in places like the card game Magic: The Gathering. You have to very carefully and artificially design a language (or example) to avoid being Turing-complete.

    (I also find it amusing that people cite 'but there's so many possibilities, how can you say anything!' against me, and then turn around and approve of a toy example 'but there's so few possibilities, you have to be wrong'. Make up your minds, already. They can't both be right. Either mechanisms are so locked-down that there is almost no variation possible, or they're so wildly common that no real sampling could've been done by evolution.)

    [–]SyncoBeat 0 points1 point  (3 children)

    The constraints on evolutionary paths are general and widespread. My example is not fragile. It's true that as genome size increases, there are more ways to get from A to B...but then you have to wait for longer amounts of time, because the path lengths are longer, and we've left the realm where "Algernon's law" was even supposed to be applicable, that is, "quick fixes".

    [–]gwerngwern.net 0 points1 point  (2 children)

    but then you have to wait for longer amounts of time, because the path lengths are longer, and we've left the realm where "Algernon's law" was even supposed to be applicable, that is, "quick fixes".

    The path lengths may be longer, but how can you know that that alone will push things out of Algernon's law territory? You can't, because you are raising hypotheticals and teapots-in-orbit-around-Mercury possibilities.

    [–]SyncoBeat 0 points1 point  (1 child)

    You don't know, you have to look at specific cases. But what I'm saying is not comparable to teapots around mercury, that's a ridiculous comparison. It does show that the premise "evolution would have found any easy fixes" is wrong.

    And that's why Algernon law is a bad rule of thumb.

    [–]gwerngwern.net 0 points1 point  (0 children)

    You don't know, you have to look at specific cases...And that's why Algernon law is a bad rule of thumb.

    As 'a bad rule of thumb', you should be able to provide many cases where it fails. Otherwise, if you can only provide a few or none, then it seems like an awfully good rule of thumb.

    [–][deleted]  (1 child)

    [deleted]

      [–]SyncoBeat 0 points1 point  (0 children)

      Which basic misunderstanding is exemplified in my post? I'm not even disputing most of Gwerns article, which is mostly good, just the idea that "evolution would have found all the easy fixes", which is bunk a priori.

      [–]api 1 point2 points  (9 children)

      There's usually no global optimum, or at least none that can be discovered in reasonable time with "reasonable" being the age of the universe.

      Even if there were, it would be a moving target. The environment is always changing, and evolutionary changes also change the environment via social feedback, sexual selection, epigenetics, development, etc.

      Generally only "toy" multi-dimensional optimization problems have stable global optima. Real-world n-dimensional optimization problems are searches for something that passes some criteria, and one never knows how close one is to a theoretical maximum.

      The fact is that there may be any number of intelligence hacks out there. We cannot prove there are, or that there are not, nor how many there might be.

      [–]gwerngwern.net 0 points1 point  (8 children)

      There's usually no global optimum, or at least none that can be discovered in reasonable time with "reasonable" being the age of the universe.

      And no reason to expect us to do much better in finding simple yet extraordinarily effective interventions which also increase fitness etc.

      Even if there were, it would be a moving target. The environment is always changing, and evolutionary changes also change the environment via social feedback, sexual selection, epigenetics, development, etc.

      I don't understand why you're bringing all those up - all of which are speeding up adaptation to the environment! That's even the apparent point of epigenetics and sexual reproduction, allowing even faster adaptation to environmental conditions and parasite arms races etc.

      [–]SyncoBeat 0 points1 point  (7 children)

      And no reason to expect us to do much better in finding simple yet extraordinarily effective interventions which also increase fitness etc.

      If we remove "extraordinarily" from this sentence, then is it wrong. There is at least one reason to expect this: humans can search for interventions that evolution can't, because we can find optima that are made inaccessible, or at least harder to find, by epistasis.

      This is covered in a vague way by Bostroms third "loophole" but you invalidly state that, for example, piracetam can't be using this loophole because "the brain could already be pushing the buttons piracetam pushes". You are assuming without justification that evolution would push those buttons if they were beneficial, but this is wrong, as I have already explained. (See the example above.)

      [–]gwerngwern.net 0 points1 point  (6 children)

      If we remove "extraordinarily" from this sentence, then is it wrong.

      And if you remove "not" from the sentence "I am not dead", I apparently am an insane person with Cotard delusion. Funny how that works.

      You are assuming without justification that evolution would push those buttons if they were beneficial, but this is wrong, as I have already explained. (See the example above.)

      How does piracetam act that cannot be done via tweaks to existing pathways? We don't understand piracetam perfectly (not that we understand any drug perfectly), but what it does seems to be straightforward tweaks of receptors to increase acetylcholine: https://en.wikipedia.org/wiki/Piracetam#Mechanisms_of_action So... what? Is there some terribly profound reason that no mutation can possibly affect acetylcholine, acetylcholinic receptors, or acetylcholinesterase even though they're modified by countless different pathways inasmuch as acetylcholine is one of the main neurotransmitters?

      [–]SyncoBeat 0 points1 point  (5 children)

      OF COURSE MUTATIONS CAN AFFECT THOSE THINGS. That doesn't mean the mutations are beneficial by themselves, although they might be in conjunction with other mutations at other places. AND IT HAS NOTHING TO DO WITH WHETHER USING PIRACETAM INCREASES FITNESS.

      [–]gwerngwern.net -1 points0 points  (4 children)

      OF COURSE MUTATIONS CAN AFFECT THOSE THINGS.

      Thank you.

      [–]SyncoBeat 0 points1 point  (3 children)

      Look, you just don't see what I'm saying, you're just making cheap one liners and talking about Turing completeness, making general remarks about the combinatorial power of mutation, and so on. I won't keep responding to this stuff.

      The key point is this: genotype B can be fitter than genotype A, but any one of the following can be true: All, some, or none of the mutations taking A closer to B are deleterious.

      [–]gwerngwern.net 0 points1 point  (2 children)

      Look, you just don't see what I'm saying, you're just making cheap one liners and talking about Turing completeness, making general remarks about the combinatorial power of mutation, and so on. I won't keep responding to this stuff.

      If all you can do is yell, then I don't mind...

      The key point is this: genotype B can be fitter than genotype A, but any one of the following can be true: All, some, or none of the mutations taking A closer to B are deleterious.

      Which is not something I have ever denied and is a restatement of evolution finding local optima and not global.

      [–]TheRegularDude 0 points1 point  (0 children)

      I'm not sure if I'm someone who can testify the validity of the points you're making, but certainly interesting connection between different ideas. Major kudos for an entertaining and informative post (regardless of if the point you're driving towards is correct or not).

      [–]ohsnapitsnathan 0 points1 point  (0 children)

      I think, for this to make sense, you have to ignore all the simple ways we've come up with to improve on evolution.

      For example, there's every infectious disease we can now treat with antibiotics or antivirals. We've been in an evolutionary arms race with pathogens for thousands of years and the way they interact with our cells and immune systems in unbelievably complicated ways, and despite an enormous amount of selective pressure we don't have good innate defenses against many kinds of dangerous pathogens. Yet many of these infections can be cured by the administration of relatively simple and well-understood molecules.