Descartes & Hume's Theory on Knowledge

Knowledge is the things that one has taken into itself and made the decision to believe that it is true. This leads to the question, what makes certain obtained pieces of knowledge true? Descartes would doubt everything until he came to an absolute and undeniable truth. If he had any reason to doubt something, it could not be true knowledge. Descartes then discovered one thing that he could not doubt and that is “I think, therefore I am.” He says that if he can think, then he knows that he exists.
I agree and disagree with Rene Descartes theory of how we have knowledge. Just because you have doubt about something does not necessarily mean there is no knowledge of it. What one may doubt, another person may have knowledge of. So is that person’s knowledge false? I say no. There are many situations like that. One may doubt the existence of God, but I do not doubt it. Since we all have our own beliefs, it does not mean one is wrong. So I do not agree with him saying there is no knowledge of things that he has the slightest doubt about. I do agree with his famous line “I think, therefore I am.” If one has the brain activity to think, then yes they do exist and that is certain. Since I am thinking, then I do have knowledge that I certainly exist. On the other hand, if one is in a coma then I still do believe that they exist. If you are living, breathing and your heart is beating then you without doubt exist even though you are not really thinking. One in a coma does have the ability to think once out of the coma so therefore they still exist.
Hume was an empiricist and he believed that all knowledge comes through experience. If you want to know anything about what the world is like, you have to go out and explore; you cannot simply sit, think really hard and hope to come up with knowledge. He believed, along with the fact that knowledge is learned through experience, that a person's experiences are nothing more than the subjects of his or her own perception. The knowledge of anything comes from the way it is observed through the five senses. Hume began to differentiate between feelings and thoughts. Feelings are only impressions made upon the body, and thoughts arrive from impressions; meaning you cannot have feelings on things you have not experienced.
I do agree that one can gain knowledge through experiences, but also through being taught what we learn in school. In order for us to be taught things in school one had to experience the scientific study, math equation or whatever the material consisted of. People did not just come up with these facts on his/her own. They spent a lot of time researching and experiencing them to gain knowledge about whatever they learned. We do gain knowledge from things we experience on our own as well. The saying “People learn from their mistakes” is the perfect example. A child touches a hot stove and burns their hand, in doing so; they learn not to touch it because they will remember what happened. In this case, they do learn from an experience.