Evolution and morality, pt 1: the instinct to kill
If we are to work towards an objective understanding of morality, and more specifically a scientific understanding that justifies thinking of moral codes as being good or bad, then the best way to start is to perceive morality through an evolutionary lens. Let’s assume for the sake of argument—as surely we must—that there is nothing about our human morality (taking certain precepts, like “thou shalt do no murder”, and so on, as being broadly representative of this) that is superior or inferior to the morality of other species, real or imagined. We only really need one assumption to compare different moral systems in a way that affords no room for subjectivity: they all evolve, and those that are unsuccessful will not last very long.
We might then look at the situation more closely at possible moral systems, and assess them for their survival-effectiveness. We can say, for instance, that a certain species has an inclination towards certain things, a disinclination towards other things, it produces a certain amount of offspring per mother, and so on. A successful moral system, then, is taken initially to be one which holds all these inclinations and disinclinations, and a number of other factors, in such a balance that allows the species to survive. An even more successful system is one which allows an even more complete thriving of the species. With this in mind we can very quickly rule out any moral system which contains a universal inclination towards indiscriminate killing, since there is no other inclination or factor which can cancel out the effect of this. If all members of the species only think about killing, we can be certain that, even with some protective instincts to counter this, the balance will always be in favour of the killing, and therefore it is an unsustainable instinct.
Even if we limit the indiscriminate killing to a smaller section of the population, there is no clear way to counter its effects. Let’s say that it is only the males that have the indiscriminate killing instinct. Unless the females are considerably stronger than the males, the killing instinct will clearly triumph. However, if the female is indeed considerably stronger, then it is reasonable to suppose that evolution will weed out the killing instinct soon enough, since it is literally useless (in that it is never used). This last point, I think, is made even more certain when we consider the dimension of sexual selection. It is not absurd, in itself, that the females will choose a male partner that kills indiscriminately (since we are assuming such an instinct is there anyway, so they have no choice), but equally, given that we are assuming that the females have a protective instinct (otherwise their superior strength would not be an issue), it would be unreasonable for them to choose the indiscriminate killer over the doting father (or the slightly less indiscriminate killer). If that last point requires a modicum of intelligence on the part of the female, then we can at least assert that those couples that don’t contain a killer will have a greater rate of survival than otherwise, and so in due course an instinctive aversion in the female towards these killers will develop.
What if only the females are indiscriminate killers? This seems even more unlikely than the previous alternative, since presumably the females will have a level of protectiveness over their offspring. The same arguments apply, however: if the male is considerably stronger than the female, the instinct would be rendered useless and thus be eradicated, and if the female is stronger, then there is nothing to stop it killing its own young.
We can say with some certainty, then, that an instinct for indiscriminate killing, whether in all of the species or only in one sex, would never survive the pressures of natural selection, and thus, in a possible perfect moral system, indiscriminate killing cannot exist. So far, so obvious, as we have only dealt with killing, which has obvious effects on survival. But in coming posts we’ll take a look at other inclinations, like those towards stealing, raping, saving another’s life, believing in God, and so on.
To be continued.
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3 comments
So, in my reading of the first few sentences of your next blog entry I’m noticing a shift in terminology from this post to that. I find this to be slightly problematic.
You used the term “indiscriminate killing.” This is certainly a type of murder, but not all murder is indeed “indiscriminate.” You then shift, in the first paragraph, to “[instinct to] murder.” I agree with your conclusions about indescriminate killing, without reservation. However, I am not entirely sure that I agree those same conclusions, having been made of a subset of “murder,” therefore apply to all “murder” equally.
Certainly, we can assume that with few very rare exceptions all human beings who do survive, do so because they desire to. We can also assume that it is entirely possible that any given human being may or may not be perfectly aware of how his actions will affect his survival… that is to say he could very easily commit an act without realizing or understanding that it will make him more likely to die.
The first question we should ask is, “Do murderers (whether they pick their prey deliberately or not) want to die?” I think, as with theft, we can assume that murderers want to live. There is some reward for murder, otherwise there would be no desire (be it instinctual or developed) to commit the act. Whatever that reward is, the murderer would not be able to partake in it if he is dead. I think we can assume, then, that the end goal of murder (in the vast majority of cases) is not to end the murderer’s own life.
If we successfully make the determination than murderers don’t want to die, it’s certainly no leap of logic to assume that non-murderers also do not generally want to die. If most people don’t want to die, is it reasonable to assume that any attempt to murder them will be met with violent consequence? I think it is. Therefore any act which would threaten the life if a man who presumably wanted to live would put the life of the “murderer” at great risk.
I think that in this way, murder in general, versus simply “indiscriminate killing,” will also will itself out in terms of natural selection, though the process may be a little slower.
Again, I totally agree with your conclusion here, I just don’t agree that it translates in the way that you think it does… there should be a smidge more support, lest we find ourselves committing the fallacy of composition.
Thanks for pointing out that distinction. I probably did jump a little too readily in the second post.
Although I like your argument ruling out the instinct to murder in general from evolutionary success, I think there is one weakness in it. If we are ruling out the “indiscriminate” part, then there is no reason that murderers might not simply be extremely choosy about their victims. So they will take into account the potentially violent consequences of killing a particular person and thus only go for the easiest targets. In this way, it will still be possible in principle to avoid this instinct dying out.
However, it will probably still balance itself out in roughly the way outlined in the post. If these “skilled” killers are also good defenders of themselves, then they will not choose to kill each other, and so eventually everyone without the instinct will be killed. Then the “skilled” killers will have no one to kill, so the instinct or the species dies out. (Or perhaps the instinct is refined, but the outcome is the same.) If the skilled killers are not particularly good at self defence, then there is no reason for the instinct to be naturally selected (apart from perhaps sexually?), and so the instinct, again, dies out.
In any case, I’m starting to think that speaking of the instinct to murder might be wrong in the first place, simply because it seems almost unbelievable that there could ever be such an instinct. Perhaps it would be better to talk of an aggressive instinct, and whenever an animal kills a member of their own species, it is simply the aggressive instinct trumping the instincts that would prevent them from doing so. The question would then become, “could it redound to the benefit of the species if this was a common occurrence?” Perhaps a more difficult question…
[...] the place of indiscriminate killing in the evolutionary realm was comparatively clear, and the place of theft was a little more muddied, then the place of rape is considerably more [...]
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