Revisability, Reliabilism, and A Priori Knowledge Critical Paper

Rocco D’Ambrosca: 04/28/2010

The subject of a priori and a posteriori knowledge has been one of the oldest problems in philosophy. A priori is defined as knowledge gained through reason without the need for experience; while a posteriori is defined as knowledge gained through experience (A priori meaning, “prior to” and a posteriori meaning, “subsequent to”, both in reference to our acquisition of knowledge). The greatest dispute has been in identifying examples of each and trying to draw distinction between them. Albert Casullo in his article, “Revisability, Reliabilism, and A Priori Knowledge” tries to address the topic of a priori knowledge in an attempt in, “(1) providing an illuminating characterization of the concept of a priori knowledge; and (2) providing cogent reasons for believing that some of our knowledge is indeed a priori.” It will be shown here why he has failed and why everyone before him and after will continue to fail at capturing a characterization of a priori knowledge and in proving that any knowledge is a priori. In short, it is the simple definition of a priori knowledge that prevents any such knowledge from existing.

As stated in the introduction, a priori is defined as knowledge without experience, while a posteriori is defined as knowledge through experience. Casullo in his attempt to explore and analyze the concept of a priori knowledge through the epistemological lenses of revisability and reliabilism, defines a priori knowledge as, knowledge acquired independent of time. He is forced to do this based on the general definition of a priori knowledge as that which is known without experience. Since all experience happens through the passage of time, for something to be known without experience it must be known independent of time. Hence, for a priori knowledge to exist we would have to exist separate from time or else all knowledge is based in experience and a priori is a worthless synthetic nonexistent concept.

The easiest defense I can use is what has been called, “The Helen Keller Thesis.” The HKT in short is an argument for the validity of sensory experiential knowledge as the only basis from which we gain knowledge in our lives and a direct condemnation of the skepticism originated by Rene Descartes. For those not familiar with the historical person of Helen Keller, she was a woman born in 1880 who became both blind and deaf at the early age of 19 months. Having lost the absolutely most crucial human senses for the acquisition of knowledge, she was forced to learn everything through her sense of touch. Her teacher would trace individual letters of words into her hand along with the corresponding thing represented by the word; early examples include a toy doll and running water. The force of the HKT is that without the window of touch sensation, Helen Keller would not have gained much if any knowledge, proving the absolute monopoly of knowledge acquisition through sense experience.

Now what does the HKT have to do with a priori knowledge? Absolutely everything! The HKT shows that knowledge is attained through sense experience. Since this is the only way knowledge can be attained, how could we know something without experience? My opponents in this argument will bring up the topics of mathematical knowledge and Descartes cogito, but here again I must insist they are confused.

On the topic of mathematical knowledge they will say that they can know 2 + 2 = 4 without any experience and that a triangle has no parallel lines with a sum of 180* all a priori. But how can they know this without experience. They must have had an experience where someone showed them these concepts in concrete terms before they were able to internalize them and manipulate these calculations at will in their mind. Someone must have shown them a set of objects and demonstrated the concept of addition; two apples plus an additional two apples equals a new sum of four apples. They must have experienced this demonstration where they gained the knowledge of addition, numerical symbols, sums, etc as concepts. The same goes for the triangle. They must have had an experience where someone drew a triangle on a chalk board, dry erase board, or sheet of paper with ink or pencil. They were shown through experience what a parallel line was so they could identify the presence or the absence of it. They were also shown how to use a protractor to measure the angles of the triangle. All of this together has formed the definition and conception of a triangle in their mind so that no matter where they see it again they can recognize it.

On the topic of the cogito as presented by Descartes, we have the same problem with experience. Descartes greatest revelation to philosophy was, “Cogito ergo sum”, translated as, “I think therefore I am.” To an epistemologist this is the holy grail of a priori knowledge that unfortunately I must smash against the wall. I do not disagree with Descartes and truly commend him for one of the absolute universal truths we have as philosophers, but I cannot in good conscience accept this as a priori knowledge. The very act of his thinking this through and reflecting in meditation upon all his experiences of doubting his senses and his absolute moronic confusion between dreams and reality, for one all takes place in time as an experience, and second does everything to show that it is an a posteriori piece of knowledge; just as all knowledge is. All of our thoughts and mental calculations, whether in mathematics or epistemological proofs, are all based on our past experiences. Without those experiences we have nothing to go on. And above all else, without the experience of gaining language or any other symbolic system to store our thoughts and concepts, we would have no knowledge but that of our animalistic instincts. And even then, those instincts are also based on past experience. We experienced hunger, ate, and then experienced fullness. We experienced absence of pain and then experienced the presence of pain. We experienced tiredness, experienced sleep, and then experienced wakefulness; etc, etc, etc.

Everything we do and know is based on our experiences. The human brain and by extension human knowledge is a slave to our biochemistry and psychology. We gain knowledge through our experiences and our ability to compare those experiences through our capacity for memory. Any confused idea of the existence of a priori knowledge is ignoring the absolute blatant fact that we would be empty of knowledge if it wasn’t for the experiences we have or the experiences we have through others by reading their works, listening to them lecture or any other means we have to communicate our knowledge to others. The very conception of a priori and a posteriori as opposites truly baffles me and should utterly frustrate any other reasonable person.

A priori knowledge, as it is defined, can only exist to God, who has always existed and who already knows all things absence of time and therefore absence of experience. It is the very definition and confused differentiation between these two synthetically created opposites that has caused such confusion and dispute for so long. Epistemologists must recognize the truth of the unnecessary and arbitrarily imposed distinction between a priori and a posteriori. They must realize that only a posteriori knowledge exists or they will be doomed to repeat the fruitless and absolutely futile endeavors that Casullo and countless others have painfully endured.