The Argument from Reason by C.S. Lewis

Here in this first short video clip, philosophers, Victor Reppert, Jay Richards, and Angus Menuge explain C.S. Lewis's Argument from Reason. Reppert wrote, C.S. Lewis' Dangerous idea, his blog can be found here. There is a very interesting interview with Menuge on Apologetics 315 (audio, transcript) and here's an article by Richards. 

Dr. William Lane Craig discusses C.S. Lewis and his argument from reason:

The Argument from Reason is what I call an argument from human experience or human nature. The basis for this argument may include any number of human experiences. Francis Schaeffer, who is noted for 'taking the roof off,' surveys the implications of naturalism/materialism in his trilogy, The God Who is There, He is There and He is Not Silent and Escape from Reason. His main criticism against atheism is the inconsistency of atheist philosophers and how it lacks the basis for almost everything that we associate with being human, moral ethic, meaning, rationalism, love, beauty, art, justice, etc.

The Argument from Reason (AFR) is closely associated with the Transcendental Argument for the Existence of God (TAG). In Total Truth, Nancy Pearcey explains that AFR leans on common sense realism, but other philosophers such as Cornelius Van Til opt for a more Bible based premise, of which human reasoning is viewed as unreliable. It was implemented by Greg Bahnsen in his famous debate with atheist, Gordon Stein.

Wikipedia's entry on the Transcendental Argument:

They are also distinct from standard deductive and inductive forms of reasoning. Where a standard deductive argument looks for what we can deduce from the fact of X, and a standard inductive argument looks for what we can infer from experience of X, a transcendental argument looks for the necessary prior conditions to both the fact and experience of X. Thus, "I entitle transcendental all knowledge which is occupied not so much with objects as with the mode of our knowledge of objects insofar as this mode of knowledge is to be possible a priori." (Immanuel Kant, Critique of Pure Reason, Introduction, VII). 

The transcendental argument attempts to prove that God is the precondition of all human knowledge and experience, by demonstrating the impossibility of the contrary; in other words, that logic, reason, or morality cannot exist without God. The argument proceeds as follows:

1. If there is no god (most often the entity God, defined as the God of the Christian Bible, Yahweh), knowledge is not possible.
2. Knowledge is possible (or some other statement pertaining to logic or morality).
3. Therefore a god exists.

Notice the quote by Kant. As you can see, the argument goes back a long time; Alvin Plantinga pointed out that Charles Darwin himself recognized the dilemma he was placing himself in. Plantinga has developed his own argument, the Evolutionary Argument Against Naturalism (EAAN), in which he demonstrates that "the probability that our minds are reliable under a conjunction of philosophical naturalism and naturalistic evolution is low or inscrutable." Wikipedia now has a full page entry devoted to the argument (here). There is also a lecture that Plantinga gave that is available in mp3.

Glenn Peoples devotes several podcasts explaining Plantinga's philosophy of Properly Basic Beliefs, Presuppositional Apologetics and EAAN (1, 2, 3 & 4), they are well worth listening to. Plantinga's argument is subtle and can be confusing to people, including atheist, Daniel Dennet, who thought he was trying to disprove naturalism and evolution with his argument. EAAN is actually quite modest, in that it only questions the underlying assumption of our ability to think rationally if our thoughts are in fact derived from natural evolution. It is a defeater for believing in the philosophy of naturalism and evolution together, but not necessarily some form of evolution such as theistic evolution.

Angus Menuge has put together what he calls the Ontological Argument from Reason. He develops a three step argument for theism providing the only basis for knowledge. First Menuge offers the following requirements for reasoning and argues that all are incompatible with materialism:

A) A conscious self that is united at a time.
B) A conscious self that persists over time.
C) Subjectivity.
D) Teleology.
E) Intentionality.
F) Libertarian free will.

The second step is the Summary of the Ontological Argument from Reason:

(P1) Reasoning requires a unified, enduring self with irreducible subjectivity, teleology, and intentionality, and with libertarian free will.

(P2) None of these resources belongs in a materialistic world.

(C) Reasoning cannot be located in a materialist world: if materialism is true, there is no such thing as reasoning.

His conclusive statement sets up the reasons for holding to Christian theism:

1) Reason cannot be located in a materialist world.

2) If reason did emerge from matter, it could not be relied on.

3) If we are made in God’s image, yet live in a fallen world, we can account for reason, its reliability, and its limitations.

(Menuge also presents a logical argument for #3 in his power point presentation and goes into more detail about his premises.)

Wintery Knight put together a pdf version of a paper Menuge gave at the Evangelical Philosophical Society (paper, debate with P Z Myers).

Here's another helpful resource page that I discovered while putting this article together: Reasons for God.