Ontology Recapitulates Philology
Much of the debate about evolution turns on language, and there is much misrepresentation, mostly on one side of the debate. Darwinists assert that "evolution is a fact," when what they really mean is that "Darwinism is a fact," but they don't want to assert that explicitly. They misrepresent their narrow theory of evolutionary change as synonymous with evolutionary change understood more broadly. They do so for several reasons, including the unfavorable connotations of Darwinism and the paucity of evidence and logic to support Darwin's radical assertion.
The truth is that Darwinism is not the same thing as evolution. Evolution is the theory that living things change over time. So understood, evolution is obviously true. There are several theories as to how evolution happens.
Darwinism is the theory that evolution lacks teleology -- changes in organisms over time have no goal or purpose. Biological structure and function is the product of differential survival of chance variations. Chance and necessity. "Chance" in the Darwinian lexicon means "without teleology."
There are several camps on the Darwinist side: there are adaptationists, who believe that most or all evolutionary changes are the result of natural selection, and the drifters, who believe that much evolutionary change is neutral with respect to selection. Both agree that the variation on which selection acts or doesn't act is non-teleological. The debate between adaptationists and drifters is acrimonious, and, in my view, witless. Natural selection applies to all evolutionary change -- adaptive, drifting, and designed. Survivors always survive.
There is a school of "theistic evolution," which asserts that God played a (subtle) role in guiding evolutionary change. Theistic evolution is a cornucopia of viewpoints, usually vague. Theories of theistic evolution are generally stated with such imprecision as to render them sentiment rather than science. They are generally poor theology as well.
Teleological theories of evolution come in two strains. Intelligent design theory asserts that the most reasonable explanation for some aspects of evolution is a process of design analogous to human design. There are some theorists who agree that evolution is teleological but take exception to the "extrinsic" design implication of design theory. These theorists are Thomists who represent the Catholic view of evolution. They see evolutionary change as a manifestation of Final Cause, as understood by Aristotle and Aquinas. They view teleology to be intrinsic to biological change and in fact intrinsic to all changes in nature. Both intelligent design and Thomist approaches to evolution are teleological; they differ in the metaphysical understanding of teleology.
In battles of ideas, ontology recapitulates philology. Truth recapitulates language. The philological issues -- the language of the debate and the meanings assigned to words -- determine in large part the truth we see. In the debate over evolution, the meanings are subtle, and they have been misrepresented (by Darwinists). The reason for the misrepresentations by Darwinists is ideological. Darwinism is indispensable to "intellectual fulfillment" in atheism, and it is defended, without regard for truth.
The truth in the debate about evolution turns largely on the meaning assigned to the terms of the debate. But it's a mistake to conclude that the truth about evolution is impenetrable. In evolutionary biology, the facts are fairly obvious. Evolution means changes in living things over time. There have been substantial changes in living things over time, and biological structures and functions have obvious purposes. Biology is saturated with purpose, as is all of nature. Nothing in biology makes sense except in light of teleology.
In my view, it's fair to say that there are two true things about evolution:
Evolution occurs, and it is teleological. The evidence for each of these assertions is overwhelming, and each is a fact.