Reality is a very subjective affair. I can only define it as a kind of gradual accumulation of information; and as specialization. If we take a lily, for instance, or any other kind of natural object, a lily is more real to a naturalist than it is to an ordinary person. But it is still more real to a botanist. And yet another stage of reality is reached with that botanist who is a specialist in lilies. You can get nearer and nearer, so to speak, to reality; but you never get near enough because reality is an infinite succession of steps, levels of perception, false bottoms, and hence unquenchable, unattainable. You can know more and more about one thing but you can never know everything about one thing: it’s hopeless. So that we live surrounded by more or less ghostly objects— that machine, there, for instance. It’s a complete ghost to me— I don’t understand a thing about it and, well, it’s a mystery to me, as much of a mystery as it would be to Lord Byron.