This “Rational Person” observed that humans have an instinct for altruism. They decided this was Rational. So they tried to intellectualize this instinct. Surely a simple formula must explain it? They settled on the formula max(pleasure-pain). But oops! Their formula doesn’t actually match human altruism. Humans care more about friends and family than insects. “Hm weird. Is my formula wrong? No! Humans are Irrational. They must change their instincts. That way my description of their instincts will be correct. That way they will be Rational. Like me. I am so Rational.”