WHAT IS DISTANCE?

Distance is nothing to fear. As early as the year 1700, Bishop George Berkeley wrote of distance that it is simply a direct line from the eye out through space. Distance cannot be seen; therefore, it should not be strained after. Distance is but an act of judgment based on memory of former experience, a comparison by imagination, a reasoning out process from which we can conceive of space and objects out in space. For example, when we are travelling on a ship, if the water is calm and there is no land or other object in sight by which to compare and make our estimates, the horizon will draw in about us very close, the mind having nothing upon which to base its estimate of space and distance. If, however, there is a lighthouse a few miles away, then beyond that a ship, the horizon pushes back farther and farther and we realise how truly far away it is. Our former experience tells us that the lighthouse, looming large, must be close and the ocean liner, appearing very small by contrast, must be far away; since we know that an ocean liner is, in reality, much larger than the lighthouse. Distance, we realise, makes the optical illusion. Distance is, then, a mental estimate, not a sense of sight; a problem for the mind, not for the eye resting on an object. Bishop., Berkeley, so many years ago, stated Dr. Bates's principle that vision is an unconscious activity, that we cannot command our eyes or turn them in any certain way or do anything consciously with them to make them see distance because that is a mental thing, an act of judgment or analysis which must take into consideration all the, facts the eye can present, and organise them within the mind.

You must be able to know mentally how different a man would look from the distance of a mile as compared to his appearance at a distance of ten feet. There would be a seeming difference in size, distinctness, faintness, in mass, in detail. So you must use your imagination to decipher or make out that it is a man and not a post, but a man seen at a greater distance.