What is the concept of completeness?

Take the animals of your world, study them, set them in order, from the smallest insect to the largest and strongest beast, and you will have before you a subject worthy your deepest consideration. 

In each and all you will observe a certain amount of instinct or intellect, corresponding to their varied structures. 

You see the ant, a very small creature, building his house with skill and displaying forethought by laying up in store provender for the coming winter. 

Here you have exemplified one of the most important features of man as a rational being. 

Then look at the little mole and the larger beaver both exhibiting in some measure the powers of engineering and building in man. Take again, the spider, and you have the skilful, industrious weaver, for, as the fishermen of earth construct nets to catch fish, so do these little animals weave their nets to entrap the unwary fly. Then on earth you have your birds of passage—these may be called the mariners of the skies. 

Even in the fish of the sea you may perceive something similar to that which meets your eye amongst men, for here is one who, finding a shell vacated by another, therein takes up his abode and keeps it.

Indeed, bring all the various classes of animals with their varied instincts and habits under your observation and you will find that all these are developed in mankind—each and all form part and parcel of man, so that when he leaves the body to go into the spirit world he carries with him the instincts or intellect of all classes of the animal creation. 

Here we have all that you have on earth—all much superior in character, but all in strict correspondence with that which exists with you in the material world and of which you are cognisant by your bodily senses.

—Hafed, Prince of Persia