The reason why we ‘know what we know’, also called epistemology, has fascinated scientists and philosophers of science from Ancient Greek society onwards. First theories of epistemology put more emphasis on absolute, unchangeable factors and character, while later on throughout the scientific revolution its belief changes to a more adaptive and active one. Plato, like his mentor Socrates, used different and completely new methods than his predecessors in order to find answers for concepts such as the nature of reality, man, mind/soul, knowledge, being and becoming. In his work The Republic he employs metaphors and dialectic prose in order to describe his theory of reality (including the world of forms) and his doctrine of Recollection. His later thoughts on epistemology went on to question all of the accepted traditional Greek beliefs on intellectual society. The abstraction in Plato’s philosophy, which was triggered by using his own inquisitive nature connected with the Socratic method, becomes most evident in his allegory of the cave, the doctrine of recollection and his theory of forms. The allegory of the cave suggests several ideas that formed Platonic philosophy. The allegory describes the way that mankind is limited, through perceiving with the help of our senses, and the way humans accept truths by a mere observation or experience rather than being based on logic and reason. The effect of man’s self-shackling, by observation rather than reason, is described in Book VII of The Republic. The philosopher sees humanity as: ‘living in a underground [den] which has its mouth open towards the light and reaching all along the den; here they have been from their childhood, and have their legs and neck chained so that they cannot move, and can only see before them, being prevented by the chains from turning round their heads’ . Even though Plato does not give a definite explanation or example or reality, he believes that in order to achieve deeper knowledge of reality, that society and man must seek to get rid of our ignorance’s and see the ‘light’. When ignorance is lifted and man has survived the hard path to the sunlight with temperance, patience, and practice; only then will we find the path to true knowledge. Plato believed that until society starts questioning the moral, political and ethical status quo, our conscious as individual and as a society would remain constricted much like the prisoners are in their lives in the cave. But the allegory of the cave was not the only way that Plato reflected on epistemology. Plato’s theory of Forms consists on the notion that all things that exist in this world are merely shadow/one characteristic of the true embodiment of the form in the empirical world. For example a small red table, sharing certain physical characteristics in common with a large white table, is not a real table, but the perception of the abstract ‘table’ in which the white table and all other tables mimic . This way of thinking was widely followed by most people until the 17th century, when Ren?? Descartes, the proclaimed father of modern philosophy, came up with his own method. He rejected Plato’s idea of using our senses combined with our previous knowledge to make sense of the world. Descartes believed the senses to be deceptive which, is why he wanted a theory on which all intellectual enquiries could be built on, so he adopted the method of doubt to reach the truth. As a big believer in reason, he felt that it should always be followed in order to conclude any philosophical truth. The method of doubt, worked on the basis of never accepting any statement or fact as the truth. In order to find the truth, one must reject everything that can be doubted, with the exception of one’s own existence ‘I think, hence I am’ and the existence of God. Through this method he tried to reach for the truth in philosophy. The Method gets rid of all beliefs that are uncertain and only the beliefs that are true remain. Descartes firmly believes that a universal nature is necessary, since he argues that it is not possible to free us of all errors that the human mind has already retained. In order to explain the process of selecting and retaining the good ones and getting rid of the bad ones picture a basket of apples. It is a faster process to empty the basket completely, so it can be cleaned and getting rid of the stains from the bad apples, and then proceeds to fill the basket with good apples. Because this way we use hyperbolic thought to doubt, it is the best approach to disregard everything and start afresh. Even though the human kind retains and remembers past incidents, Descartes believes that our senses are very easily perceived and distorted. It is not easy to accept that the world we know is an illusion and only through deep introspective thoughts, humans are able to accept that God is true, and it is he that fixed that thought into our minds. The best approach to investigation, to arrive at the knowledge of truth is using the Method of Doubt. In striking contrast to both epistemologies of Plato and Descartes stand those from John Locke and David Hume. Both Locke and Hume are known as British empiricist because they emphasize the role of the senses and the experiences we can through our sense in the acquisition of knowledge. John Locke explicitly rejects the idea that all knowledge is gained through sensory experiences. He believed that the mind was a blank slate when one is born. He states in the beginning of his essay: Let us then suppose the mind to be, as we say, white paper, void of all characters, without any ideas:–How comes it to be furnished? . . . Whence has it all the materials of reason and knowledge? To this I answer, in one word, from experience . This quote emphasizes that sensor experiences such as vision, hearing, smell, and touch put an impression on the mind and convert then to be our knowledge of the world. Because of the role that sensory experiences played a part in Locke’s epistemology it is a mostly instructional epistemology but an inopportune one. Even though he believed that our senses are the origin of human knowledge, he makes it clear that one should not assume that they provide accurate information on all aspect of the external world. The source of most ideas that pertain to the external world, he referred to as sensation. Within that he distinguished between the primary and secondary qualities of things. In the primary things such as shape, weight, number, and movement were included, whereas the secondary included color, taste, smell, texture, and temperature. He argues that for the primary qualities or sense guide as and the knowledge retrieved from the experience is always true. But this is not the case for the secondary qualities. For example the taste or color of an apple are sensations that are a produced by the object but do not reflect the properties within it. Locke’s idea of secondary qualities reflects the important recognition that even our perception of the external false can be fooled and it does not indicate the actual state of the world. Yet in admitting this fact, he paved the way for others to doubt anything that we perceive in the real, material world at all. Where John Locke used the senses to perceive and acquire knowledge David Hume, who was impressed by Newton’s experimental method to discover the truth, used a more scientific and empirical approach. While Newton had success using the more scientific approach, resulting in his discovering the laws of physics, Hume’s attempt to do the same and replicate such success only led him to an inescapable and distressing conclusion. Locke’s epistemology is based on the experiences that one has gained of the world through the use of their sensory experience and the knowledge that an external world and its characteristics exist. Hume states that empirical procedures were the only means of obtaining factual knowledge, it was impossible ‘ strictly speaking ‘ to deduce universal causal laws from the evidence of the senses . He recognizes that because the ideas that we have of an external world are generated by th
e perceptions that, we acquire through our sensory experiences we will never have true knowledge of an external world. Hume argues that the belief that external objects exists, despite the irrationality of it, is strictly due to the human nature which compels us to believe this. He concludes that sensory experiences can reveal anything of a material, external world even though humans are at the core irrational in their beliefs. He realizes that no amount or kind of sensory experience, which is trustworthy depending/limited to a context, time and place, would only be able to result in a justifiable knowledge, though impossible by instruction, of the generalizations or laws of nature. It is inescapable that all human knowledge will not contain a possibility of error, no matter the amount of experience, logic or reason behind it. All human knowledge must be fallible; by revealing this irrationality of human belief based on sensory experience and reflections on them he effectively destroys empiricism.
“Book VII.” In The Republic, by Plato, 25. Excerpt from Intellectual Origins of the Contemporary West. Compiled by Queen’s University Department of History. 3rd ed. Vol. 1. Boston, MA: Pearson Learning Solutions, 2012. 25-30.
2 “Book VI.” In The Republic, by Plato, 24-25. Excerpt from Intellectual Origins of the Contemporary West. Compiled by Queen’s University Department of History. 3rd ed. Vol. 1. Boston, MA: Pearson Learning Solutions, 2012. 19-25.
3 “Part IV.” In A Discourse on Method, by Ren?? Descartes, 350. Excerpt from Intellectual Origins of the
Contemporary West. Compiled by Queen’s University Department of History. 3rd ed. Vol. 1. Boston, MA: Pearson Learning Solutions, 2012. 389-361
4 “Chapter 1: Of Ideas in General, and Their Origin.” In An Essay Concerning Human Understanding, by John Locke, 375. Excerpt from Intellectual Origins of the Contemporary West. Compiled by Queen’s University Department of History. 3rd ed. Vol. 1. Boston, MA: Pearson Learning Solutions, 2012. 375-382
5 In David Hume, by David Hume, 383. Excerpt from Intellectual Origins of the Contemporary West. Compiled by Queen’s University Department of History. 3rd ed. Vol. 1. Boston, MA: Pearson Learning Solutions, 2012. 383-393
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