Depends. Sometimes from a cultural standard. Sometimes from a subconscious standard that I am not paying attention to. Sometimes from a standard that I make up.
Ok, but I don't understand how Agrippa's trilemma applies.
Here it is: When you decide with reasoning as per free will, when you check reason, it is not free. It ends up being a dogmatic belief - that is the want in the video.
It connects to that end standard for choosing between A and B, ends up being a want in favor of one of them and thus against the other.
Here it is for wants as measurement:
"Man is the measure of all things: of the things that are, that they are, of the things that are not, that they are not."
When you then check how measurement works, you end with the fact that it connects to this debate and how reasoning works.
All of this can be done without science and with philosophy just as in the video.
You are not observing thinking and free will. You are checking how it works and if it has limits. Just as mobility is limited, so is thinking and in the end, thinking is limited by being the result of something else. Genes and neurology.
So now ask this - how can something which can't be observed to have free will, genes and neurology, cause free will, which in effect is un-caused? Free will is causation ex nihilo.