The absolutist position is rather straightforward and presents the fewest possibilities for contradiction. According to the absolutist, there exists an absolute moral code which a person can know, but which some people (for whatever reason) don’t know. When a person doesn’t know or understand the principles of this moral code, they don’t know right from wrong and can be declared legally insane.
To hold such a position, the following premises must be accepted as true:
1. There exists an absolute moral code, independent of humans.
2. This moral code is knowable.
3. We know this moral code.
4. Every moral principle from this code is reflected in our laws.
5. None of our laws reflect any principles which are immoral under this code.
6. A person who does not know true “right from wrong” is legally insane.
From these premise, we are able to arrive at the following inferences:
7. A person who breaks the law also violates the absolute moral code.
8. A person who adheres to any moral principles not in the law is not adhering to the absolute moral code.
Taking all of the together, we can arrive at this conclusion:
9. Anyone who violates the law because they really believe that they are following a higher standard of morality does not really know true “right from wrong” and, hence, is legally insane.
This is a valid argument and it is pretty easy to follow. The argument is also very strong because the lines between “sane” and “insane” are sharply drawn. The only problem here is, no one really believes this argument. True, there are plenty of people who accept premises 1-3, particularly religious people who believe that their god had actually delivered such a code to humanity. Others offer secular arguments in defense of at least premise #1.
Not everyone believes premise #3, however — even some religious people are unwilling to argue that humans know the entirety of this absolute moral code. There is even more widespread agreement in the rejection of premises 4 and 5. Religious people in particular will reject those premises because our secular laws so often do not reflect their religious ideals.
Thus, it is possible for someone to use the absolutist position to defend the validity of an insanity plea, but it is very unlikely that you will encounter someone who will try to do it. It isn’t even likely that you will find someone doing it for the sake of argument, much less because they actually believe it.
There is a slightly modified version of the absolutist position which is a bit more common. This position simply eliminates premises 4-5 and inferences 7-8 and results in a private judgment rather than a legal one. Thus, anyone who violates the absolute moral code (which I know) and honestly believes that they were not because they were following some other, false moral code must be insane.
This has the advantages of being reasonably strong, logically, and being something which people actually believe. The disadvantage, however, is that it is a private judgment. This is not an argument suitable for legal decisions — jurors can’t be asked to decide whether or not the defendant has violated what they believe to be the “absolute moral code” without truly understanding that they have done so.
