Descartes’ conceivability argument:

It is conceivable for me to exist without having a body.

Whatever is conceivable is possible.

Therefore, it’s possible for me to exist without having a body.

If it’s possible for me to exist without having a body, then having a body is not essential to me..

Therefore, having a body is not essential to me.

It’s inconceivable for me to exist without having a mind.

Therefore, it’s impossible for me to exist and not have a mind.

If it’s impossible for me to exist without having a mind, then having a mind is essential to me.

Therefore, having a mind is essential to me.

The Divisibility Argument

If minds are identical to bodies, then whatever is true of minds is true of bodies, and vice versa.

But minds are indivisible and bodies are divisible.

Therefore, by the principle of indiscernibility of identical, minds are not identical to bodies.