Time has a great influence upon all things and beings, as may be seen by the change from infancy to youth, and from middle age to old age. In Sanskrit, therefore, time is called kala, which means destruction, as no change is possible without destruction; in other words, destruction may be described as change. All things natural and artificial that we see today differ vastly in their form from what they were several thousand years ago, and not only can this be noticed in such things as fruit, flowers, birds and animals, but also in the human race; for from time to time the structure of man has undergone various changes.