Full Idea
Even if we suppose God had united a body and a soul so closely that they couldn't be closer, and made a single thing out of the two, they would still remain distinct, because God has the power of separating them, or conserving out without the other.
Gist of Idea
Even if tightly united, mind and body are different, as God could separate them
Source
René Descartes (Principles of Philosophy [1646], I.60)
Book Reference
Descartes,René: 'Philosophical Essays and Correspondence', ed/tr. Ariew,Roger [Hackett 2000], p.247
A Reaction
If Descartes lost his belief in God (after discussing existence with Kant) would he cease to be a dualist? This quotation seems to be close to conceding a mind-body relationship more like supervenience than interaction.