How to experience Anatta Is it during deep meditation when the mind is completely stilled that one experiences anatta? Is the conviction in anatta gradual or abrupt? This question would be connected to the 4 stages of enlightenment, too.

Regards
Anatta can be seen even by the average Joe. Ex: when there's headache or any kind of bodily pain, why it is not going away at will?  When you taste something, why the taste disappear after eating? Why can't you make the taste persist. Why your body stink when you don't take bath? Why can't you stop that from happening? When happiness arises in the mind, why does it fade away without your consent?