Chapter 2 of the Philosopher’s Way was about the concept of substance. I always thought the the concept of substance was the same thing as what the next chapter is entitled “Being, Essence, Reality”. It was too easy to reduce. This quote keeps sticking out to me “Where you find a contradiction, make a distinction” that's just an aside though.
I guess I was confused because substance is like a mode of being (THE primary mode of being) or description?
Anyway, there are 3 main things to take away according to Wahl.
The relationship between a substance and its properties. There is always a dialectic (Which I think is ultimately reflected in his monist vs pluralist focus) between conceptions of the two. The problem arises when we try to justify the most basic feature of reality, something in or for itself, and how if it is truly basic, how can it have properties that are also fundamentally part of it. At least this was the problem for a long time
We have to choose a level of experience to view substance from. I believe here he means the metaphysical, as we see it up to Kant. And then we either move to a logical, social, or psychological point of view.
That substance may be an outdated concept. It is okay and still knowledge to accept that your knowledge of something is limited. We can either apply to the openness of feeling which is in a way independent of other knowledge claims, and science. (I think my intuition leads me to think this is what Deleuze means by a logic of sense. There is also science and art which provide the ther main form of intelligence.
Wahls frames his historical dialectic again (Or he’d claim history did) between the spiritual and the ‘rational’. The Pre-Socratics didn’t bother with this. But also that substance has always been dual starting with them. Both Thales and Heraclitus put either the water separate from the gods or Fire above the Logos respectively. This is developed in Plato, who inspires Descartes to take it further and not just have dualism as a feature of substances but with substances. Even though he technically has 3. Kant changes the game a little bit by making it one of his a priori categories, but still keeps the theoretical aspect of substance.
Then a whole bunch of people decide its time to move past substance. Wahl endorses a social and phenomenological account of it. Okay! Time for reality!
(I seek more to describe Wahl’s ideas I pick out here, and my understanding of the individual movements in the blog posts).