The “Lazy Aristotle” Fallacy
Otherwise known as “confusing the natural with the common” or “the ‘normal’ equivocation”. The word ‘normal’ signifies at least two different terms or concepts that are entirely distinct in themselves, even though they might be related in very fundamental ways (hence the confusion). Here are the two senses I have in mind and as I would distinguish them:
Normal1 = what is the most frequent; what is common; whatever happens the majority of the time.
Normal2 = what is normative (i.e., what should or ought to be the case).
Here is an example that at once shows the difference between these two senses and also that there is *no* reason to think that they must coincide.
Suppose the world’s water supply is contaminated in such a way that it makes every single dog have three legs or, if a certain dog has yet to be born, it is born with only three legs. It seems to me that in the sense of normal1, the following statement would be true:
(1) It is normal for dogs to have only three legs.
If the ‘normal’ in (1) means frequent, common, or what happens the majority of the time, then of course it is true. How could it be the case that each and every dog has only three legs but and it not be ‘common’ for them to have only three legs?
But clearly, even though (1) might be true in the normal1 sense it is patently false if taken in the normal2 sense. That is, even though it might be the case that all dogs have only three legs, it most certainly is not the case that all dogs should or ought to have only three legs. On the contrary, as Aristotle would put it: it is the nature of a dog to have four legs, and therefore all dogs should have four legs.
The basic upshot is this. Suppose that some act F happens most of the time. Nothing follows about whether F should happen most of the time. And vice-versa. Suppose F ought to happen. Nothing follows about whether F will in fact happen all of the time or even most times.
Here are some more putative cases where normal1 and normal2 most certainly do not coincide:
From what I hear, binge drinking is not uncommon on college campuses, yet it seems that binge drinking should be uncommon.
Binge drinking is at best normal1 but not normal2.
Prior to the Civil War, slavery in the South was very common, yet it should not have been.
Slavery was normal1 but surely not normal2.
In 1930’s Germany anti-Semitism might have been common, yet if it was, it should not have been.
Anti-Semitism may have been normal1 but surely not normal2.
What is especially vexing about the fallacy is that you often hear people using some fact about what is normal1 as evidence to think that the act in question is normal2, which either equivocates on the two senses or begs the very question at hand or both. Here is an example:
(2) Homosexuality is wrong because it is not normal.
The inference here is something like this:
(3) Homosexuality is not normal.
(4) Therefore, homosexuality is wrong.
If ‘normal’ means normal1, then this argument is invalid. As we have seen before, just because F is not common, it does not mean that F-ing ought to not take place.
If ‘normal’ here means normal2, then sure enough the argument would be valid, but then it would be begging the question. For to say that F-ing ought to not take place is tantamount to saying that F-ing is wrong.
I call this the “Lazy Aristotle Fallacy” because Aristotle was prone to thinking that what happens “either always or for the most part” was indicative of a thing’s nature, where “nature” here is to be understood as the “what it is to be” of a thing—its essence (as opposed to “that place people go when they go camping.”) Since Aristotle was thinking of natures as essences, they are the kinds of things that ground normative claims. But, as we have seen, it is not at all clear the connection between what is common, what is natural, and what ought to happen, much less how we ought to move from one to the next, even if it is very common for us to do so.
All this to say that I think this fallacy is nothing short of a rampant intellectual disease that has infected most of the human “sciences” (e.g., psychology, cultural anthropology, sociology, psychiatry, and the like). I also think that failing to recognize this fallacy is one of the major confusions behind the ever shifting faces of the various forms of relativism.