Well, that mostly sounds good ... except your actions seem to contradict your words? From what I can tell, he wants to look at porn, and he thinks there is not

Well, that mostly sounds good ... except your actions seem to contradict your words? From what I can tell, he wants to look at porn, and he thinks there is nothing wrong with it. Whatever the conclusion of your conversation with him was, he is obviously not convinced that he shouldn't, at best he ends up expressing agreement because he is dependent on you. The only reason why he now does it without you knowing and without any possibility of discussing with you when he sees something that disturbs him is that you force him to, not because he agrees with you. You say that you are not authoritarian, but your actions say the opposite. Either you are exercising power or you are not, whether you dress it up in nice words, doesn't change whether it is authoritarian. Now, you constantly repeat that you want to protect him from danger, and I guess some of your authoritarian behaviour may hinge on that. After all, authoritarian action is somewhat justified if you know that without it, harm will follow. The problem is that based on what you have written here, you don't know that. You have referenced some extremely unscientific ideas and sources and shown some biases that suggest that you are not rationally evaluating the actual risks and dangers of your child's wishes and your authoritarian responses, but are probably more acting based on your own emotional response. The danger that you are imagining most likely isn't there, but the damage that you do by restricting your child in order to protect him from this imaginary danger is real, both in that it is damaging his trust in you, and in that you are making him internalize that his probably perfectly healthy sexual curiousity is a problem that he has to fight against.