In 1921, Einstein, while discussing the significance of mathematics in the development of scientific thought, remarked `` .... an enigma presents itself which in all ages has agitated inquiring minds. How can it be that mathematics, being after all a product of human thought that is independent of experience, is so admirably appropriate to the objects of reality? Is human reason, then, without experience, merely by taking thought, able to fathom the properties of real things? " Fifteen years later, he went on to say, ``The very fact that the totality of our sense experiences is such that by means of thinking...it can be put in order, this fact is one which leaves us in awe, but which we shall never understand. One may say `the eternal mystery of the world is its comprehensibility' (Kant)."

Has evolution shaped us for reasoning? Would there have been some form of Darwinian selection that gave an advantage to those with the ability, or at any rate, the trait that would lead eventually to the ability, to make a model of reality in the brain. This evolutionary advantage, amplified over time, has led to the human brain that has great skill in describing the world. At the same time, then, the brain has also retained all those features that helped it along the path and gave selective advantage, and among these could be those attributes of the human mind that we find so difficult to describe and define--- creativity, imagination, emotion, philosophy, and religiosity, for instance. Therefore, argues Hamming [10] in an insightful article on the effectiveness of mathematical thought, ``we can cope with thinking about the world [only] when it is of comparable size to ourselves and our raw unaided senses.... Evolution, so far, may possibly have blocked us from being able to think in some directions; there could be unthinkable thoughts".

What about other, thinkable, thoughts? If evolution has ensured the development of the human brain with its billions of interconnected neurons to be capable of mathematical thought, are there other aspects of consciousness that are similarly the product of evolution? Indeed, perhaps the sense of soul has also conferred evolutionary advantage, bringing us to this stage of humanness.