>How does that even make any sense? You can turn the exact experiment around, there are people who have brain damage to the areas of their brain that let's them reason logically, but they still have intact moral behaviour.

I didn't point you to a source that talks about the physical aspect of psychopathy just the qualitative aspect. You're going to have to find that yourself on google it's easy to find.

Suffice to say that people who have psychopathy have either damage to the exact same area of the brain or a lack of nerve connections in the exact same area of the brain. Researchers have identified the exact physical location for this in the brain. If I recall correctly it's actually at the front of your brain above your eyes. Look it up.

>By that logic, logic itself is not logical because there's an area in the brain that can be turned off? Then nothing is logical because practically every function of the brain can be missing.

All areas of the brain can be turned off and on and damaged. There are tons of experiments and recorded cases in psychology about this. Literally tons, in fact it makes up a huge portion of the field of psychology. Psychologists understand the brain through people who have suffered damage from it. Here's one case of a woman who cannot feel fear: https://www.wikiwand.com/en/S.M._(patient)#:~:text=S.M.%2C%2....

Additionally we can even turn "on" parts of the brain. One of the treatments of depression involve "turning on" or stimulating a specific part of your brain with varying amounts of electricity. See: https://www.nami.org/About-Mental-Illness/Treatments/ECT,-TM...

It's not an off or on switch... more of a volume control but even that is a blunt description of what's going on.

>You haven't shown that morality is instinctual, you have shown that morality happens in the brain, which big surprise as I said is true by definition.

I have shown it's instinctual. Let me walk you through the reasoning. If the moral part of the brain suffers damage you are no longer moral, but you can still reason.

If you can still reason then if morality wasn't instinctual you can still be moral by your reasoning alone. However we have shown that by killing a part of the brain that doesn't affect your reasoning and creating psychopaths who can reason but cannot be moral we have shown that morality isn't part of reasoning.

>Why is it supposed to follow from the fact that psychopaths exist that morality is "instinctual", or "born"? Rather than that they've lost their ability to reason about moral subjects?

Wrong. Psychopaths can reason about moral subjects. Boolean logic and logic itself is universal and they can still reason that way. They just don't care to follow that reasoning, because morality itself is not logical. A psychopath can identify the behaviors we classify as "good" and the behaviors we classify as "evil" but he does not have an emotional response when plunging a knife into someones face. In short when the opportunity is advantageous to him, the psychopath will not hesitate to kill. Usually though, such actions are never advantageous, so the psychopath remaining logical to the core, will often not kill throughout his entire lifetime.

The words "Good" and "evil" at it's most logical essence are just words that classify certain behaviors and actions... there is no true logical existence of either word beyond its usage as categorization. To a true Neutral intelligence of pure logic and reasoning "good" and "evil" are just arbitrary categories that are made up by human culture and behavior. A psychopath is just closer to a neutral intelligence than a regular human being.