Full Idea
It would be wrong to represent Descartes' view as the idea that bodies are made of one kind of stuff and minds of another; he did not think minds are made of stuff at all, because then they would be divisible.
Gist of Idea
Descartes did not think of minds as made of a substance, because they are not divisible
Source
Tim Crane (Elements of Mind [2001], 2.10)
Book Reference
Crane,Tim: 'Elements of Mind' [OUP 2001], p.38
A Reaction
I'm not convinced. It could be an indivisible substance. Without a mental substance, Descartes may have to say the mind is an abstraction, perhaps a pattern of Platonic forms.
Related Idea
Idea 5011 There are two ultimate classes of existence: thinking substance and extended substance [Descartes]