Descartes believes that all of our mistakes occur as a result of our arrogance – because we think or pretend that we can know things that we cannot know.

Descartes refers to Aristotle’s four causes or kinds of explanations:

• Firstly, we can answer the question by referring to the material that something is ‘made out of’. For example, ‘the table is hard because it is made out of wood’. (This is known as a material explanation.)

• Secondly, we can explain something in terms of a formula, rule, or definition. For example, ‘This shape has 3 sides because it is a triangle’; ‘Dave is a bachelor because he is an unmarried man’. (This is known as a formal explanation.)

• Thirdly, we can give an answer that relates to the cause, or causer of the event or thing. What causes something to happen? For example, ‘The pencil is on the floor because Dave dropped it’; ‘the snooker ball moved because it was hit by the cue’. (This is known as an efficient explanation.)

• Fourthly, we can explain something in terms of purpose or function, in terms of reasons. For example, ‘he went to the supermarket because he wanted bread’; ‘the knife is sharp so it can cut things’; ‘I am late because I wanted to go to the toilet.’ (This is known as a final or teleological explanation.)

The concept of a final cause was taken up and adapted by Aquinas during the Mediaeval period. In effect, the notion was christianised. Whereas Aristotle thought that the purpose of a thing could be derived from the characteristic powers it happened to possess. There was no need for an explanation in terms of a designer.

Aquinas couldn’t countenance such an idea and had to attribute all purposes to God. In one of his arguments for the existence of God he wrote:

Given this understanding of a final explanation, Descartes believed that we should not concern ourselves with it. Descartes thought that it was arrogance to think that we could know what the purpose of things was. That would be tantamount to knowing the mind of God.

For Descartes, the whole universe should be viewed as a huge mechanism, like a great mechanical clock. According to him, it isn’t our job to understand why it is like it is, it is only our job to know what it’s made of, how it works, and most importantly, the rules that govern it all.