Descartes says that he resolved that anything he thought of was just something that was happening in a dream. Can you do what Descartes says he did? That is, can you convince yourself that right now...

Descartes says that he resolved that anything he thought of was just something that was happening in a dream. Can you do what Descartes says he did? That is, can you convince yourself that right now you are having a dream and that everything you are doing or thinking at this moment is just part of your dream? Is there any way that you can figure out for sure that you are not having a dream right now?