Deductive logic teaches us that the acts of reasoning and knowing are inseparable from the act of negating. To understand the law of non-contradiction (a thing cannot be and not be at the same time) is to also understand its reciprocal principle, the law of identity (a thing is what it is and not something else). If we know what cannot be, we also know, in a complementary sense, what is. As the legendary Sherlock Holmes reminds us, “Once you eliminate the impossible, whatever remains, no matter how improbable, must be the truth.”
On the subject of God and Evolution, for example, there are two competing models, but only one of them can possibly be true. In order to provide a meaningful overview, I will use common terms in my abbreviated summary of each model so that the differences relevant to our discussion will become evident:
{A} Traditional Theistic Evolution acknowledges two Divine creative strategies. (1) Through a purposeful evolutionary process, God “forms” man’s material body from the bottom up, and (2) By means of a creative act, God “breathes in” an immaterial soul from the top down, joining spirit with matter.
{B} Contemporary Christian Darwinism recognizes only one Divine creative strategy. Through a natural evolutionary process, God “allows” all of man’s physical, rational, and spiritual traits to emerge from the bottom up and does not, under any circumstances, intervene from the top down, even to infuse a soul into a pre-existent human.
Can we say with apodictic certainty that one of these paradigms is false and, by extension, that the other one is true? If we assume that God exists, and if we assume that rational souls exist, and if we assume universal common descent is a valid theory, then the answer is yes. Reason dictates that a bottom-up, evolutionary process, though it may be responsible for the development of lower living forms, cannot, by any stretch of the imagination, produce a rational soul. In other words, Christian Darwinism is, without question, a false world view. To be rational, then, one must either embrace Traditional Theistic Evolution or reject macro evolution (universal common descent) altogether.
But how do we know that Christian Darwinists are wrong when they assume that matter can evolve into spirit? To begin with, we must take note of the way Christians differentiate between these two realms of existence: material entities, such as bodies, brains, and organs are physical entities and contain parts, which means that they can disintegrate, decay, die, or be transformed into some other kind of matter (or energy, perhaps); spiritual entities such as souls, minds and faculties, are non-physical entities and contain no parts, which means that they cannot disintegrate, die, or be changed into something else.
Clearly, a material body (or brain), which will die and change into another kind of matter, cannot evolve into a spiritual soul (or mind), which is unchangeable, contains no parts, and will live forever. If then, spirit is to be joined with matter, its origins cannot come from matter or from a material process; it must come from another source, that is, it must come directly from God, who creates spirit and implants it in a pre-existing being from the top down.
Even So, Christian Darwinists, without a modicum of embarrassment, hold that matter can, through incremental evolutionary changes, make the leap from dust to eternity. While materialists argue that molecules can come from out of nowhere and then re-arrange themselves to produce organic life; Christian Darwinists argue that molecules can re-arrange themselves into a spiritual soul that contains no molecules. I will leave it to the reader to discern which of these two propositions represents the greater threat to the standards of rational thought.
For a Christian to make sense of evolution, he must, if he accepts universal common descent, and if he accepts the transcendent nature of the soul, envisage some process by which God, at the right stage in the evolutionary process, implanted the soul into a pre-existing human being. The process itself simply cannot make the voyage. For rational theists, no gradual development from lower animal forms to human rational souls can be admitted.