Philosophy...what do you think?

Reading a book on decartes who claims he was not going to use his senses to prove (something), just intelligence/ideas/etc......My question to any of you philosophy ppl is....How can you use intellect to create ideas/thoughts without using pre-existing senses....If you had NONE of your senses (no touch, taste, feel, smell, sight) you could not even think of any ideas...you would basicly be nothingness. Correct?