I grew up in a scientific world, the son of a neurosurgeon.

We can only see what our brain’s filter allows through.

I understand what happens to the brain when people are near death, and I had always believed there were good scientific explanations for the heavenly out-of-body journeys described by those who narrowly escaped death.

Laughter and irony are at heart reminders that we are not prisoners in this world, but voyagers through it.

I had a foretaste of another, larger kind of knowledge: one I believe human beings will be able to access in ever larger numbers in the future. But conveying that knowledge now is rather like a chimpanzee, becoming a human for a single day to experience all of the wonders of human knowledge, and then returning to one's chimp friends and trying to tell them what it was like knowing several different Romance languages, the calculus, and the immense scale of the universe.

There is no scientific explanation for the fact that while my body lay in coma, my mind - my conscious, inner self - was alive and well.

I finally chalked it up to the fact that the brain is truly an extraordinary device: more extraordinary than we can even guess.