Do you trust your reasoning abilities? Can you? The answer to the latter question depends very strongly on your answer to the first. Here is the problem: You cannot defend your reasoning abilities without appealing to them. Any attempt you make to defend your reasoning abilities will inevitably require you to use them. Therefore, that you can trust your reasoning abilities is an axiom. A starting point. The beginning of a circle. I'm basically saying that every argument you make will always be circular reasoning. And yet, circular reasoning is a fallacy, is it not? "My reasoning skills tell me I can trust my reasoning skills" is logically identical to "my Bible tells me I can trust my Bible".
Do you trust your clock? Can you? In many cases, the answer might be no. Clocks can break, clocks can wear down, clocks can be tampered with, it is entirely possible that your clock is telling you the wrong time. But because clocks are designed to tell you the right time, it's also entirely possible your clock is telling you the right time.
Do I trust my reasoning abilities? Can I? I believe so. See, as a Christian, I believe I was fearfully and wonderfully made by the infallible God. I was designed with the capacity to reason, or at the very least my species was. We were commanded to fill the earth, subdue it and have dominion over it. We were told to study to show ourselves approved, and to test all things and hold onto that which is good. We were designed to relate to our God, and His word tells us that His creation "declares His handiwork", and that what may be known of Him is clearly seen in creation. Science itself was founded on Christian assumptions. The philosophy of experimental science, as Loren Eilsley said (1), began its discoveries and made use of its methods in the faith, not the knowledge, that it was dealing with a rational universe controlled by a Creator who did not act upon whim nor interfere with the forces He had set in operation. Science owes its origins to an act of faith that the universe can be rationally interpreted, and that science today is sustained by that assumption. So, can we trust our reasoning abilities? If the Bible is true, yes!
But what if Charles Darwin was right? What if we weren't really created by an all powerful, all knowing God who designed us to think rationally? If the universe began with a magical explosion, if our planet just happened to form in the right place in the randomly formed universe, if life really did just pop out of unintelligent slime... What if we really are just apes? Could we trust our reasoning abilities then?
Look around you. You are surrounded by living things that do just fine without any kind of reasoning skills. My dog is a bit of a doofus. My cats can be distracted by a laser pointer. Put a chimp in a lab coat, what can it do? I don't think giving a microscope to a dolphin would move us one inch closer to curing cancer. As Darwin himself once said, "But then with me the horrid doubt always arises whether the convictions of man’s mind, which has been developed from the mind of the lower animals, are of any value or at all trustworthy. Would any one trust in the convictions of a monkey’s mind, if there are any convictions in such a mind?" (2)
And would you? If we could communicate perfectly with a monkey, do you imagine it could tell you more than a well educated preschooler? Right now, I am doing more than a monkey ever could. I'm not just typing coherent sentences, I'm contemplating my own existence. And because you are a literate, presumably rational human being, you are reading coherent sentences and contemplating your own existence. This is not something any other physical creature would ever think to do.
There is no such thing as design in Evolution. If you want to add a god into it, fine, find me a god who fulfils all the requirements (omniscience, omnipotence, omnipresence, complete honesty), then we'll talk about it. But until then, you're either left to make such a god up, or to just stick with atheism. In this case, you can at best reason that your brain can accurately assess truth claims that provide you with a reproductive advantage. Even then, the truth does not always keep you alive. Sometimes, a lie might be just as effective, if not more. In fact, this is the very origins story Evolutionists gave for why Theism is so prevalent in the human race. Religion, they claim, kept our ancestors alive! All that to say that if Evolution is true, you have no reason to believe you can accurately assess any truth claim.
So, philosophically speaking, which is the superior worldview? The religion that makes your intelligence as valuable as a gibbon's, or the religion that inescapably leads to the conclusion that mankind has both the ability and responsibility to accurately assess truth claims?
The only way to make Evolution compatible with the accuracy of human reason is to add a god. That god must be omniscient, or it would suffer the same problem: How can it trust its reasoning capabilities? It must be omnipotent, or how could it build all this? It must be omnipresent, or it would be incapable of sustaining reality outside of its area of influence. It must be honest, because put simply, when you add an almighty deceiver into the mix, there is no end to the tricks we could fall for. As I like to say about the "greatest of deceivers" (Allah, see Qur'an 3:54; 7:99; 8:30), "if you cannot trust his word, you cannot trust his world".
But let's say you've found such a god. Maybe there's some obscure religion out there somewhere that preaches a god who is omnipotent, omniscient, omnipresent and 100% honest. Great, now it has to compete with the Lord God of Israel, Jesus Christ. See, the God of the Bible is unique. He's the only God who puts His money where His mouth is. God not only stepped into history, but He told us a heck of a lot about it beforehand. History testifies of Christianity's veracity in a way no other religion can claim. Christianity is the only religion that can boast of a 0% fail rate when it comes to prophecy, and it is the only religion that can claim our God walked the ground and breathed our air.
And this is where we get to the central claim: The Gospel. We rebelled against our Creator, a crime that demands death. But whose death it requires is negotiable. The sinner can die for their own sins, but God offered an alternative: Jesus took the punishment for our sins. Jesus died, Jesus rose. The resurrection proves His divinity, but is also the way in which His grace is received. By confessing Him as Lord and believing He rose, our sins can be separated from us as far as the East is from the West. Or you can continue in your rebellion against your Creator until the day you meet Him, against all logic and reason. May the Holy Spirit regenerate your heart and empower you to take the obvious choice.
References
1. Eiseley, Loren. - Darwin’s Century: Evolution and the Men who Discovered It, Doubleday, Anchor, New York, 1961
2. Darwin, Charles - Letter to William Graham, 1881