What is the difference between A Priori and A Posteriori? What are analytic and synthetic statements?

What is the difference between A Priori and A Posteriori statements or arguments?

A Posteriori statements are statements or truths ‘post experience’. In other words, you have to have experienced something in order to make the claim. Remember it because ‘post’ means after – after experience.

A Priori Philosophical statements are based on logic

A Priori statements are usually ‘analytic’ in nature and A Posteriori statements are usually ‘synthetic’ in nature.

What is an analytic statement?

An analytic statement is one that is analytically true i.e. it is true within itself. An example of this is the term ‘bachelor’. A bachelor is an unmarried male. The term bachelor entails ‘maleness’ and ‘unmarriedness’.  If you told me ‘John is a bachelor’ I would not have to meet John to know that he was unmarried and that he was a man. That is because the term ‘bachelor’ itself tells me these things analytically.

What is a synthetic statement?

A synthetic statement is something that is true by the way it relates to the world. For example, ‘the cat is black’ is a synthetic statement.

Now, let’s say that ‘catness’ entailed ‘blackness’, and Timmy was a cat. He would therefore be black, and this would be analytic. However, not all cats are black.  Therefore, the statement ‘the cat is black’ is synthetic.

Is the statement ‘God Exists’ A Priori or A Posteriori?

This is a trick question, because the answer is both!

If we argue that ‘God exists’ from Design in the world (Paley), we are presenting a A Posteriori argument.  That is because I have to experience the design in the world to be able to present the argument for God as a designer.

If we say that ‘God’ exists arguing ontologically, we are presenting an A Priori analytic argument. This is because, according to Anselm, existence is a logical necessity for God.

All you need to know about the Teleological argument

The teleological argument is A posteriori, it uses our experience of ‘design’ in the world to argue for the existence of a designer – God.

Examples of this could be the sky, the human brain, even emotions – the concept would say that if things exist they must have a designer.

St Thomas Aquinas

Aquinas asserted that there were five ways to prove Gods existence, one of which is the teleological argument. He thought that the regularity in the universe shows design, which he referred to as ‘Design qua regularity’.

  • Beneficial order – things that exist work towards an end
  • Beneficial order – cant happen by chance
  • Many of the objects that work towards an end wouldn’t have the intelligence to do so by themselves
  • Therefore such objects must have been directed to do so – by God.

William Paley

Paley argues for ‘Design qua regularity’ and ‘Design qua purpose’. An example of Paley’s design qua purpose argument is the Watch Analogy. The watch analogy simply states that if you were to look at a watch and examine its inner workings so perfectly put together, in synchronicity you would never claim it just created itself – he therefore asks how on this premise could you assert the same about a human being or the world as a whole.

Modern versions of the Teleological argument.

Arthur Brown

Brown, in his 1943 book ‘Footprints of God’, examined the ozone layer and how it is the exact thickness for its purpose. He states that his shows evidence of a plan and therefore design.


Tennant puts forward the Anthropic Principle, which states that it is highly unlikely that science or evolution alone is responsible for intelligent life.

No Designer = Chaotic world

He believes that Intelligent OrderSustained Life and Intelligent Progression provide evidence to support the design argument.

Tennant also puts forward the Aesthetic argument. The ability to appreciate aesthetics has no evolutionary value, such that the only explanation as to why we can appreciate creation must be that God gave us the ability as a gift.

Richard Swinburne

Swinburne also sees the complexity in the universe and cannot put it down to mere chance – stating that the most likely explanation would be that God is the creator.

Okham’s Razor: Holds that the simplest explanation is the most likely.

There are many arguments for and against the design argument. If you are for or against the principle please comment, let us know what you think of the teleological argument.