Finding ourselves in a universe that seems bent on destroying us, we quickly discover, both as individuals and as societies, that it is a good thing … - Sam Harris

every religion preaches the truth of propositions for which it has no evidence.

I want to be clear that when I used terms such as “pretense” and “intellectual dishonesty” when we first met, I wasn’t casting judgment on you personally. Simply living with the moderate’s dilemma may be the only way forward, because the alternative would be to radically edit these books. I’m not such an idealist as to imagine that will happen. We can’t say, “Listen, you barbarians: These holy books of yours are filled with murderous nonsense. In the interests of getting you to behave like civilized human beings, we’re going to redact them and give you back something that reads like Kahlil Gibran. There you go … Don’t you feel better now that you no longer hate homosexuals?” However, that’s really what one should be able to do in any intellectual tradition in the twenty-first century. Again, this problem confronts religious moderates everywhere, but it’s an excruciating problem for Muslims.

We have names for people who have many beliefs for which there is no rational justification. When their beliefs are extremely common we call them ‘religious’; otherwise, they are likely to be called ‘mad’, ‘psychotic’ or ‘delusional’... Clearly there is sanity in numbers. And yet, it is merely an accident of history that it is considered normal in our society to believe that the Creator of the universe can hear your thoughts, while it is demonstrative of mental illness to believe that he is communicating with you by having the rain tap in Morse code on your bedroom window. And so, while religious people are not generally mad, their core beliefs absolutely are.

Just as we perceive the outside world on the basis of sensory signals met with a top-down flow of perceptual expectations and predictions, the same applies to perceptions of the internal state of the body. The brain has to know what the internal state of the body is like. It doesn’t have direct access to it, even though both the brain and body happen to be wrapped within a single layer of skin. As with perception of the outside world, all the brain gets from the inside of the body are noisy, ambiguous electrical signals. Therefore it has to bring to bear predictions and expectations in order to make sense of the barrage of sensory signals coming from inside the body, in just the same way as for vision and all the other “classic” senses. And this is what’s collectively called interoception — perception of the body from within. The same computational principles apply. In this view, we can think of emotional conscious experiences, feeling states, in the framework of “interoceptive inference.” So emotions become predictions — “best guesses” — about the hidden causes of interoceptive signals, in the same way that experiences of the outside world are constituted by predictions of the causes of sensory signals.
This gives a nice computational and mechanistic gloss to old theories of emotion that originated with William James and Karl Lange — that emotion has to do with perception of physiological change in the body and by the subsequent cognitive “appraisal” of these changes. The predictive-processing view adds to these theories by saying that emotional experience is the joint content of predictions about the causes of interoceptive signals at all levels of abstraction.