We overlook the misprints, that is, we replace the wrong letters which are actually in our field of vision by imaginary right letters which correspond to our expectations.

Are we not also familiar with the experience of supplying by our fancy the associative image of a movement when only the starting point and the end point are given, if a skillful suggestion influences our mind.

The prestidigitator stands on one side of the stage when he apparently throws the costly watch against the mirror on the other side of the stage; the audience sees his suggestive hand movement and the disappearance of the watch and sees twenty feet away the shattering of the mirror.

The suggestible spectator cannot help seeing the flight of the watch across the stage.
The recent experiments by Wertheimer and Korte have gone into still subtler details.

Both experimenters worked with a delicate instrument in which two light lines on a dark ground could be exposed in very quick succession and in which it was possible to vary the position of the lines, the distance of the lines, the intensity of their light, the time exposure of each, and the time between the appearance of the first and of the second.