A problem with the four causes is that they rely on experience. Plato argued that experience was unreliable as it changes from person to person – we cannot be sure that chairs look the same to every person. Also, Aristotle has no concrete evidence that the material world is the source of knowledge – many would turn to religion and faith as the source of truth. However, the Four Causes are derived from Aristotle’s reflections on his studies of the natural world so many would agree that they are reliable, including many scientists.
Another benefit to the four causes is that they can be applied to things which already exist. The material cause can be tested and confirmed; ‘The chair is made of wood’. The formal cause is also easy to prove – the structure of something can be seen. We can test it. The efficient cause is more confusing as there can be several efficient causes for an object. The carpenter made the chair but a wood cutter cut the tree and a machine sanded the wood. The final cause is obvious in some cases (a chair exists to be sat on) but less so in others – what is the final cause of a person?
There are anomalies which don’t conform to the four cause structure. The material cause of a movement or the efficient cause of a coincidence highlight flaws in Aristotle’s theory. If things happen by chance or luck then they do not fit into the categories. Emotions also go against the theory as they have no material or formal cause and even their efficient and final causes can be questioned. Is there a final cause for despair?
The fact that there are anomalies does not disprove the theory and this is a major strength to the argument. There is no evidence that it is not true and it doesn’t overrule