“Observation: I can't see a thing. Conclusion: Dinosaurs.”

“Telepathy’ literally means to feel at a distance, just as ‘telephone’ is to hear at a distance and ‘television’ is to see at a distance. The word suggests the communication not of thoughts but of feelings, emotions. Around a quarter of all Americans believe they’ve experienced something like telepathy. People who know each other very well, who live together, who are practised in one another’s feeling tones, associations and thinking styles can often anticipate what the partner will say. This is merely the usual five senses plus human empathy, sensitivity and intelligence in operation. It may feel extrasensory, but it’s not at all what’s intended by the word ‘telepathy’. If something like this were ever conclusively demonstrated, it would, I think, have discernible physical causes -perhaps electrical currents in the brain. Pseudoscience, rightly or wrongly labelled, is by no means the same thing as the supernatural, which is by definition something somehow outside of Nature.”

“Seances occur only in darkened rooms, where the ghostly visitors can be seen dimly at best. If we turn up the lights a little, so we have a chance to see what’s going on, the spirits vanish. They’re shy, we’re told, and some of us believe it. In twentieth-century parapsychology laboratories, there is the ‘observer effect’: those described as gifted psychics find that their powers diminish markedly whenever sceptics arrive, and disappear altogether in the presence of a conjuror as skilled as James Randi. What they need is darkness and gullibility.”

“You can get into a habit of thought in which you enjoy making fun of all those other people who don't see things as clearly as you do. We have to guard carefully against it.”

“We can't help it. Life looks for life.”

“You might imagine an uncharitable extraterrestrial observer looking down on our species... - with us excitedly chattering, "The Universe is created for us! We're at the center! Everything pays homage to us!" - and concluding that our pretensions are amusing, our aspirations pathetic, that this must be the planet of the idiots.”

“You're an interesting species. An interesting mix. You're capable of such beautiful dreams, and such horrible nightmares. You feel so lost, so cut off, so alone, only you're not. See, in all our searching, the only thing we've found that makes the emptiness bearable, is each other.”