Foundations of Knowledge: Part 2 - Rationalism and Belief in God

Rationalism is an epistemological method which attempts to ground knowledge in reason. 

Rationalism is often contrasted with Empiricism, which is the attempt to ground knowledge in sense-based experience. Rationalists argue that the variable nature of sense-based experience, that experiences of the same thing can change according to the perspective of the knower, makes it an unreliable foundation for knowledge and truth (For more on this see the video, “An Introduction to Logic and Reasoning Skills - Part 2).

In contrast reason is said to provide a more objective and reliable basis for knowledge, because no matter where you are in the world or who you are, what is logically and rationally true is always going to be true.

For instance, consider the following syllogism, which is a logical method of deducing a conclusion from what appear to be unrelated premises:

• A - All men are mortal 
• B - I am a man 
• C - Therefore, I am mortal

The basic structure of a syllogism is as follows: A + B = C. Thus we deduce: If the first statement (All humans are mortal) is true, and if I am a man, then logically it follows that C is true (I am human, male and therefore mortal).

Rationalism is also associated with the scientific method. Science largely operates according to the principle that true knowledge about ourselves and the nature of the world can be found by utilising human reason and logical enquiry. Unsurprisingly, with its emphasis on faith, belief, and supernatural revelation, religious knowledge is often considered incompatible with the scientific method and Rationalism.

An example of a so-called incompatibility would be religious beliefs about the origins of life, versus scientific theories of cosmic evolution. For instance, in the Bible in the Book of Genesis, we read how God appears to create the world in the course of a week, whereas cosmic evolution suggests that the emergence of the universe and life took billions of years.

It has been suggested that religious accounts of the creation of life were the product of pre-scientific knowledge: that stories were told to help people find a meaning and purpose in life. Thus, the more humans came to understand the world they live in, the less they needed the religious worldview to explain things and fill in the gaps. All this has added to the view that religious belief and reason cannot co-exist with each other.

But for all that atheists and scientists might want to reject religious belief and the existence of God as the by-product of an unenlightened mind, it is a mistake think that Rationalism has no place for God, or that Rationalists are naturally inclined towards unbelief and atheism.

For example, the Greek philosopher Plato who was very much a Rationalist sets out an argument in “Timaeus” for the existence of a benevolent (or Good) demiurge (god/Creator), who brought the world into existence. Although Plato’s demiurge is not the same God as the one argued for in the various modern Cosmological Arguments, there are clear parallels with these, the most notable being that a Divine presence is the First Cause of everything.

One of the most famous examples of a rationalist methodology being employed to support belief in God is Anselm’s Ontological Argument. In “Proslogion”, Bishop Anselm argues that something which exists is better (or greater) than something which does not, and so concludes that God’s existence is logically preferable to God’s non-existence. This means that God actually existing is the greatest thing we can conceive of God. He also argues that the claim “God does not exist” is logically nonsensical, for to suggest that God does not exist presumes we know what it means to say God does exist (which according to him, means God exists).

One of the more striking examples of where Rationalism and belief in God meet is in the philosophy of Rene Descartes. In his “Meditations” he explores a logical and rational method for establishing true knowledge. He suggests that whilst sense-based experience and certain thoughts about his existence can be doubted, the fact that he is having doubting thoughts cannot. Thus, he concludes that whatever cannot be doubted is true (“Cogito ergo sum”).

However, whilst Descartes was certain that his “method” set out a logical and rational basis for knowledge, he still felt the need to ground it in something other than this; something absolutely guaranteed to be a constant and reliable source of truth. And so with this in mind, the Fifth Meditation concludes: “Thus I recognise very clearly that the certainty and truth of all knowledge depends on… God.’’

Finally, Reformed Epistemology sets out a rational defense of belief in God’s existence by suggesting this belief does not require proof, as many non-believers argue it does. In rejecting the call to provide evidence for God’s existence (Evidentialism), they argue instead that belief in God should be treated as a basic and justified belief. For example, just as the existence of other minds is something we consider to be a rational and logical thing to believe, yet one we cannot actually provide evidence for to conclusively prove is true, then why not regard belief in God’s existence in the same manner? If we’re not insisting on evidence to prove the existence of other minds, then why insist that we need evidence to prove (or justify) God’s existence?