There is an amazingly silly proverb which quite mistakenly tells us that *seeing is believing.*

The most ordinary conjurer at a village entertainment will prove the falsity of this saying.

For who has not seen one of these plausible mountebanks put a watch into a top-hat, and, after clearly smashing it into a thousand pieces with a pestle, stir up the disintegrated fragments with a spoon and produce an omelette?

Or who is so unacquainted with the affairs of the village schoolroom at Christmas as not to have seen a solid billiard-ball or a lively canary squeezed out of the side of a friend’s head? Such phenomena are by no means rare, and occur periodically all over England.

The observer’s eyes have told him that he has seen such things, and the verb *to see* is merely a compendious expression to indicate that on the evidence of your eyes such or such a phenomenon has actually occurred.

But no one believes that the disintegrated watch has become an omelette though ocular evidence—seeing—insists that it has. It was a conjuring trick.

And this leads me to the consideration of the phenomena on which this whole book is based.