In the middle ages, medieval philosophers started to question Aristotle’s theory on predication. The substance plus the accident concludes the predication. According to Aristotle, the substance has an existence independent from the accident. The substance can be seen as a phenomenon with which we associate certain accidents, but these accidents can obviously vary and still represent the same substance. As an example we take the substance dog. A dog can have the accident long hair. However, it’s still a dog if you rid him of this long hair. Dogs can also have short hair or even be bald if you want to go all the way. This proves that the substance exists independent from the accident.
However, this started to become problematic when medieval philosophers applied this theory to God. In this situation, God is the substance and for example being merciful and being intrinsically good are one of his many accidents. According to Aristotle, these accidents are not necessarily connected to the substance. Therefore, God isn’t necessarily merciful or intrinsically good, which obviously caused lots of panic among strong believers.
I agree with the medieval philosophers that the independent existence of substances isn’t possible. It reminds me of meditating. I was told that to meditate you need to clear your mind completely; first think of a red dot on a blank canvas and then slowly try to exclude the red dot and only be left with a blank mind. I’ve tried this many times and am of the opinion that this is impossible. You’re always thinking of something, especially when you think of a concept like the substance Aristotle discusses; when you take away all the qualities of something, the concept disappears with those excluded qualities. Thinking of a tree without it’s leaves, wooden trunk and roots, is thinking of something completely separate from the phenomenon of a tree how we know it. Therefore, it’s absolutely justified for the medieval philosophers to reconsider Aristotle’s theory.
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