Another explanation.

After reading and accepting the ideas the person can't say. -"God has a plan for me" or "I'm on a mission from god" To see life positively one has to interpret things like -"I'm so lucky my ID created me" into -"I'm lucky to be in this small habitual space in the galaxy where the sun shines and I don't have to fear death on a daily basis."

Reviews insist it's depressing but I don't think so. I'm not going to personally go shouting at people to "accept the truth". An atheist version of a Jehovas Witness is quite similarly obnoxious.