Everyone has the ability to obtain knowledge from what he or she believes, but the question is, does everyone see and interpret the same sight of an object in the same way? Each person has a different sense of reality, a different personality and thus a unique point of view or opinion in the subject matter. Thus it is just to state that all human beings interpret information differently. These differences in perception could be considered as errors by others with other opinions.
Descartes claims that all knowledge he possesses has been acquired with or through the senses. He believes that to avoid making errors and in order to know everything we have to challenge our senses, and must relearn everything completely based on scientifically- based and proven information. In order to do this, we must break down our knowledge into steps which lead us to the conclusion of what we know or believe.
If our parents tell us a story about the tooth fairy, to us it is a source from authority, whether we believe it or not is a different matter. Information of family history could be passed down either from a recorded family tree or through what our parents told us. Thus we can say that some information from authority has been told and re-told through generations. According to Descartes, “old wives tales, myths, rumor,” and “hearsay” are all sources of information passed down through authority, and is not necessarily passed on by our parents.
A very personal example of how authority from one side of my Khairallah family (based in the village Ghbaleh, in Lebanon) led me to have a very biased source of information, deliberately aimed against someone. My mind refused to accept some parts of the following story, and so did not follow Descartes’ wish to tear down the edifice of knowledge. A few years ago, our family priest was accused by another member of the Khairallah family of stealing money from the church for personal reasons. Because my Grandparents and direct relatives were completely outraged by this idea, I was obliged to think the same. I never got the chance to fully understand the full truth of how and why a member of our own family accused another member of theft, and on what facts and basis the accusation was made.
Through this example, we can also see that because there are many points of view, and because there are various sources of information (based on different perceptions of reality of the situation), we can conclude that a source from authority is not always completely correct. Although I saw the different attitudes to the crises, and heard different points of view, there was still a problem in finding the truth. In our perception of different matters, we error because our senses tell us different things.
Another source of knowledge is from memory and experiencing different events which lead us to drawing a generalized conclusion on what we believe we saw. Conjecture (drawing of a conclusion based on previous information, knowledge or experience), belief (interpretation based on personal experience), and opinion (concluded belief based on a judgment of what we have seen or have been through) all let us believe more firmly on what we know because we have experienced it.
Comparing and contrasting information acquired from authority (usually deliberately biased sources aimed to discredit or honoring something or someone) and experience (and memories of that experience), we see the level of reliability in the different sources of knowledge. For example, if it is written in a history text book, that 10 million soldiers were killed in World War One, and on the internet, an estimate of 37 million casualties was presented, there is a clear lacking of accuracy of information from the authority. In this case, we have developed “dog-tags,” which soldiers wear in war. When one dies, his or her dog tag is taken from him or her to record number of casualties in the war. This aims on improving accuracy of information presented to us from authority, or else we will begin to doubt knowledge from this source.
Through memory, however, you base knowledge on previous experiences. For example, you don’t listen to other soccer player’s accounts of how painful an injury was, because you have felt it yourself, and so are more certain of what you know. Superstition, assumption, opinion, belief and conjecture are the ways of knowing Descartes says are from an interpretation of arthritically passed down information or of personal experience.