Is There Any Motivation for Doubt?

I'm thinking the overall sketch of assuming that we're in error about everything. It was a false argument until the nineteenth century, and then it became true. That mean we can agree to disagree about that. I think there's lots of reasons to motivate that scepticism. Saying that scientific theories are universaliations, r generalization, they're saying, in all circumstances, something happens. And i don't worry about whether things exist outside of him. But again, i think the larger point is that descartes isn't really worried about anything outside of him - he just wants you to disprove what you want to disprove.