Whether or not they are real is more a philosophical issue than a physical one. While we should presumably take seriously everything this Arkani-Hamed character

Whether or not they are real is more a philosophical issue than a physical one. While we should presumably take seriously everything this Arkani-Hamed character has to say on physical issues, on philosophical issues this is much less clear. Everybody can have his/her opinion on these. And since we seem to like to talk out of authority here you can say that a PhD in particle physics told you. I am no longer in that field now anymore, though. So maybe I am indeed more stupid.....