Your survival module seems to have a special kind of veto power in matters of belief. If something threatens your survival, safety, or security – including your financial security – the senior member of your brain committee can make it nearly impossible to believe it. Just imagine a person employed by the oil, coal, tobacco, or gambling industries being asked for their beliefs about global warming, lung cancer, or gambling addiction. “It is difficult to get a man to understand something, when his salary depends on his not understanding it,” Upton Sinclair said, and we could easily substitute the word believe for the word understand. As our brain committee navigates the constant barrage of rewards, punishments, threats, and opportunities that life presents us, our survival, belonging, and meaning modules must constantly negotiate conflicts of interest. That internal struggle often makes doubt even more difficult and costly.
From “Faith After Doubt: Why Your Beliefs Stopped Working and What To Do About It” by Brian McLaren