You shouldn't care about the "who" at all. You should see their arguments. If taxi driver doesn't know anything real, it should be plain obvious and you can sta

You shouldn't care about the "who" at all. You should see their arguments. If taxi driver doesn't know anything real, it should be plain obvious and you can state it easily with arguments rather than attacking the background of the person. Actually, your comment is one of the most common logical flaws (Ad Hominem), combining even multiple at the same time.