It is said that animals cannot behave immorally because they are incapable of discerning right from wrong. But why is this relevant? Chimpanzees murder one another on occasion, for example. If murder is inherently wrong, what does it matter that the chimps don't know it? Surely, we wouldn't allow moral ignorance as an excuse when a human commits murder. (Not to mention the fact that chimpanzees probably shun other chimpanzees who've committed murder, so how can we really be sure they don't have any moral sensibilities?) The only way I can think of this being relevant is that morality actually has nothing to do with the actions themselves, but rather has to do with how human beings relate to these actions. If murder were wrong because of features inherent in the act of murder, than chimpanzees who kill others would be just as morally guilty as humans who do so. Murder must be wrong because of features inherent to humans (as we are the only candidates for moral agency we know of), and the way we relate to murder. Ultimately, though, doesn't this mean that morality is entirely mutable, via thought or culture or even only through something radical (yet plausible) like genetic modification?

A man points a gun and pulls the trigger. The gun fires, and the bullet strikes another man in the head, killing him instantly. Was it murder? Anyone who thinks they can answer the question based on what's been said so far doesn't understand the word "murder." Did the man who pulled the trigger do something wrong? Anyone who thinks they can answer the question based on what's been said so far doesn't understand what it means for something to be wrong. Whether what happened was a murder, and whether anyone did anything wrong depends on a lot that's been left out, not least a lot about who intended to do what and who knew or believed what.

Scenario #1. The man who pulled the trigger is a hit man. The person shot was an otherwise innocent witness to a crime. The person who hired the hit man wants to be sure the witness can't testify. This murder and the man who pulled the trigger (as well as the one who hired him) did something deeply wrong.

Scenario #2: The man who pulled the trigger is a police officer, and his job is to protect a witness from being killed to keep him from testifying. The man who was shot is the hit man, and had the officer not fired his weapon, the witness would almost certainly be dead. That's not murder and it would take considerable arguing to make the case that the officer did anything wrong.

Scenario #3: the man who pulled the trigger is an actor. The gun was supposed to be loaded with blanks and has been on every one of the many previous performances of the play. But someone who wanted the victim dead tampered with the gun. This is a murder. But the murderer isn't the man who pulled the trigger, and that man is not to be blamed for what happened.

All of this is legal and moral common sense. It would be easy and might be instructive to add a bunch of other scenarios. But these few will do. Whether a bit of behavior is an act of murder depends on what was in the mind of the person whose behavior is at issue. It may not depend only on that, but it depends at least on that. The same goes for whether a bit of behavior amounts to moral and not just legal wrongdoing.

So now we come to the monkey. (Yes, I know: chimps aren't monkeys. But it sounds good.) For a monkey to commit murder would take a lot of understanding and intending that's quite likely beyond the capacity of a typical simian. We can agree that the death of the monkey is a bad thing, and that this is because of something about what it means for a creature to die. We can also agree that the death of the man in any of our other scenarios is a bad thing -- that it would have been better if no one had ended up dying. But both in the human case and the animal case, whether it's murder or whether it's a case of moral wrongdoing depends on knowledge, intent and in general what's going on inside one or more minds.

None of this gives us any reason to think that morality is mutable, shifty or culturally relative. Related points apply to behavior that doesn't raise moral issues at all. Whether a waving hand is a greeting or a signal to the waiter to bring the check or an involuntary spasm depends on what's going on in a mind or minds. If we focus on mere raw behavior and ignore what's going on in minds, we won't understand action at all, let alone actions like murder.

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