We are posting on a website that he created, and that he defined the original (and primary) scope of discourse for. But more directly: at least two people have

We are posting on a website that he created, and that he defined the original (and primary) scope of discourse for. But more directly: at least two people have called my comment an ad hominem; 'pg is arguably the single person most responsible for popularizing the dismissal of critiques as "ad hominem" among technical people[1]. Note that even he doesn't make the ridiculous claim that personal observations are inherently irrelevant. [1]: http://www.paulgraham.com/disagree.html http://www.paulgraham.com/disagree.html