I did not want to prime you with my own examples, but since you say
'give me a situation in which someone who is normally apt to have free will doesn't?' [...] my answer is 'I can't
I will try. Here are some examples where you might feel not having free will, which is an easier question to answer than objectively not having free will, since all you have to do is ask someone about what they feel and think. Note that different people are likely to give different answers.
The voices in your head tell you to stab someone and you are compelled to do it. Subcases: a) you don't want to do it, but do it anyway, b) you don't care either way and just do it, c) you don't understand what wanting or not wanting even means when the voices in your head make you do things. I'm sure there are more alternatives.
You see your arm rising and punching someone, without consciously deciding to do so. Again, various subcases are possible.
You instinctively yelp when startled, before having time to decide whether you should.
Ah, I see. It seems to me that all those examples are like my example (2), where someone has free will but is not presently exercising it (however much it may appear that they are). I agree that, on the face of it, those all seem to me to be examples of not exercising free will. One could be in those situations while having free will all the same. I could, for example, watch my arm punch someone, and yet be freely writing a note to my mother with the other arm.
ErinFlight said:
Thinking about it, I realized that this might be a common concern. There are probably plenty of people who've looked at various more-or-less technical or jargony Less Wrong posts, tried understanding them, and then given up (without posting a comment explaining their confusion).
So I figured that it might be good to have a thread where you can ask for explanations for any Less Wrong post that you didn't understand and would like to, but don't want to directly comment on for any reason (e.g. because you're feeling embarassed, because the post is too old to attract much traffic, etc.). In the spirit of various Stupid Questions threads, you're explicitly encouraged to ask even for the kinds of explanations that you feel you "should" get even yourself, or where you feel like you could get it if you just put in the effort (but then never did).
You can ask to have some specific confusing term or analogy explained, or to get the main content of a post briefly summarized in plain English and without jargon, or anything else. (Of course, there are some posts that simply cannot be explained in non-technical terms, such as the ones in the Quantum Mechanics sequence.) And of course, you're encouraged to provide explanations to others!