Reddit reviews The Slavery of Death

It actually goes deeper than that. When you challenge someone's world view, it triggers mortality thoughts. We identify with things larger than ourselves partially because it means that part of us will survive on past death. That can be a religious group, a political movement, a nation, a company, a cult, etc. Someone challenging the legitimacy, or, worse, the future existence, of our larger-than-self structures results in dire existential doubt. This is experienced as a very deep anxiety.

There's a whole psychological framework that studies how we manage those existential anxieties both in the moment and then later on. Doubling down on (affirming) one's worldview is one of those ways. People in this state also get more xenophobic, more prejudiced, and less merciful to criminals, but, interestingly, not immediately. There's a delay of 2-5 minutes before that effect kicks in.

And, fun fact: The type of anxiety this produces is similar enough to other types of pain processed by the brain that Tylenol actually suppresses it (pdf).

Edit: Link to paper, details

Edit2: The Worm at the Core is the best book I've read on TMT. My favorite amateur theologian, psychologist Richard Beck, also wrote The Slavery of Death in which he attempts to incorporate TMT into Christian theology on sin, I think very successfully.