Sam Brownback's op-ed on evolution in today's Times gets off to an interesting start, but quickly devolves into a self-contradictory muddle.  It appears intended to stake out a middle ground on evolution (hence the attempt to reach out to readers of the Times) but after a few paragraphs, he starts to gum up the works with code-words aimed at soothing his base in the intelligent design community.

At the outset, Brownback says: 

The heart of the issue is that we cannot drive a wedge betweenfaith and reason. I believe wholeheartedly that there cannot be anycontradiction between the two. The scientific method, based on reason,seeks to discover truths about the nature of the created order and howit operates, whereas faith deals with spiritual truths. The truths ofscience and faith are complementary: they deal with very differentquestions, but they do not contradict each other because the spiritualorder and the material order were created by the same God.  People of faith should be rational, using the gift of reason that God has given us.

So far, so good.  This seems consistent with the Catholic approach to faith and reason.  As John Paul II put it, "[t]here is thus no reason for competition of any kind between reason and faith: each contains the other, and each has its own scope for action."

Brownback goes on:

Faith supplements the scientific method by providing an understandingof values, meaning and purpose. More than that, faith not science can help us understand the breadth of human suffering or the depth ofhuman love. Faith and science should go together, not be driven apart.

I'm still with him.  Science can tell us how the world operates, but it cannot answer the fundamental "why" questions with which faith is ultimately concerned.  He continues:

Many questions raised by evolutionary theory like whether man hasa unique place in the world or is merely the chance product of randommutations go beyond empirical science and are better addressed in therealm of philosophy or theology.  The most passionate advocatesof evolutionary theory offer a vision of man as a kind of historicalaccident. That being the case, many believers myself included reject arguments for evolution that dismiss the possibility of divinecausality.

Again, this seems right to me.  Proper respect for science is not inconsistent with a demand that science remain with its sphere of competence and not venture into questions of ultimate meaning that are properly the domain of faith.  Moreover, while science can show many things, it cannot rule out the very possibility of "divine causality," at least in some sense.  (Of course, it can rule out some religiously-based claims about the universe, such as the assertion that the creation story in the Bible is - in a literal sense - descriptively accurate.)  It's one thing to say that human beings evolved according to the process of natural selection, but it goes beyond that to make the evaluative judgment that we are nothing more than an "accident."  Science can establish the first, but is not competent to establish the second. 

Despite these solid points, Brownback ultimately undermines his case by slipping into intelligent design code-speak.  For example, out of nowhere, in about the middle of the piece, he says:

If belief in evolution means simply assenting to microevolution, smallchanges over time within a species, I am happy to say, as I have in thepast, that I believe it to be true. If, on the other hand, it meansassenting to an exclusively materialistic, deterministic vision of theworld that holds no place for a guiding intelligence, then I reject it.

This seems like an obviously false choice.  Either limit evolution to change within species or it becomes an "exclusivley materialist, deterministic vision of the world"?  Why not a view of evolution that recognizes the common origin of species while rejecting "exclusively materialist" interpretations of that evolutionary process?  Brownback repeats his "small changes" language again later in the op-ed:

I am happy to let the facts speak for themselves. There are aspects ofevolutionary biology that reveal a great deal about the nature of theworld, like the small changes that take place within a species.

The consensus among biologists is that the data supports far more than "small changes that take place within a species."  As TalkOrigins puts it:

The worldwide scientific research community from over the past 140years has discovered that no known hypothesis other than universalcommon descent can account scientifically for the unity, diversity, andpatterns of terrestrial life. This hypothesis has been verified andcorroborated so extensively that it is currently accepted as fact bythe overwhelming majority of professional researchers in the biologicaland geological sciences

Letting the facts speak for themselves means accepting the descriptive accuracy of the theory of (macro)evolution as virtually every mainstream biologist understands it.  As John Paul II said,

"newknowledge has led to the recognition ofthe theory of evolution as more than a hypothesis.It is indeed remarkable that this theory has beenprogressively accepted by researchers, following a series of discoveries invarious fields of knowledge. The convergence, neither sought nor fabricated,of the results of work that was conducted independently is in itself asignificant argument in favor of this theory.

Far from letting the facts speak for themselves, the insistence on limiting the scope of evolution to "microevolution" is a central tenet of the intelligent design crowd.  According to the Intelligent Design and Evolution Awareness Center, a pro-intelligent design organization:

Most intelligent design proponents accept microevolution but questionif macroevolutionary changes are possible. Intelligent design theoryquestions if evolution can produce irreducibly complex structures.Thus, intelligent design holds that evolution is not capable ofproducing all aspects of life.

At the end of the day, despite his insistence on the complementary nature of faith and reason, it is clear from his op-ed that Brownback's faith informs his reason, but not vice versa.  "Facts" that contradict Brownback's preexisting faith-derived conception of the origins of the human species are cast aside as ideology.  But for faith and reason to be complementary sources of knowledge it is not enough that faith guide reason.  Reason must also at times challenge and revise how we understand our faith.  This includes the scientific consensus that species can evolve from other species.