The existence of sense data in the private space in itself poses another problem. For example, it is entirely plausible that different people can have conflicting views of the same event. If this is the case, then whose account is the right one? It can be argued, since the datum of each person exists in the private space, that each person ahs his or her own relative perception. Therefore, it can be argued (especially if Locke’s idea the mind represents but does not duplicate the world is followed) that relative realities exist since sense data differs from person to person. Yet, the idea of a relative reality creates an almost solipsist view in that my concept of reality is entirely dependent on how the sense data I receive is interpreted by my mind. Following this view, there is no such thing as an objective truth. However, this cannot be so since a proposition such as ‘all bachelors are unmarried’ does not require subjective interpretation since the idea is in itself an analytical or necessary truth.
Sense data poses yet another problem in the fact that it is a medium through which we perceive the world. If this is the case, how can we know that sense data is truly representative of the world since, following this view, there are no raw perceptions by which we can validate it. This also begs the question as to whether the physical world exists at all since there is no way that I can know whether the sense data is indeed caused by the real world.
John Locke’s view concerning representative realism was that the mind represents or makes an impression of the world through sense data, but does not mirror what is actually there. Again, it is made clear that we cannot be sure of whether what the mind has perceived is what is actually existent in the world.
Furthermore, it also appears that changed conditions give changed sense data. For example, if a person sees a field of grass in daylight, he correctly concedes that it is green. However, at night, under the hues of yellow city streetlights, the grass may appear brown. In this example, the changed conditions (the colour of light) have changed the sense data received from the grass. Why is it then, that although the grass may appear brown under yellow streetlights, we still concede that it is indeed green, contradicting the sense data we receive from it? Representative realism inevitably leads us to believe that the only things of whose existence we can be sure are sense data.
Representative realism does very well in resolving the problems of naïve realism, but does very little to affirm itself as an absolutely viable basis for our perceptions. This is because it does not still does not disprove notions such as Descartes’ malignant demon (the idea that we are all victims of a mass illusion), nor does it provide us with a means to accept that beyond any doubt whatever that sense data is a foolproof means of obtaining information from, and perfect image of, the world.
assess empiricism
Empiricists believe, unlike the rationalists, that the main source of our knowledge is derived from our senses. It argues that there are no innate ideas and that all things that we know, we know because we have experienced them through our senses. For empiricists, the mind is a tabula rasa (a blank slate) upon which all our knowledge is inscribed after we learn.
Following empiricist ideas, such as those of the Scottish philosopher, David Hume, the only things we know are things that have causal relationships, i.e. we know that releasing a ball that was formerly held in our hands would drop and bounce on the floor. From this view, it is thought that we understand the universe in terms of cause and effect. By causal means I can be assured that my releasing the ball caused it to bounce. But is it possible to still have knowledge without the conditions of cause and effect?
Empiricist would argue that since there are unlimited experiences, it is possible that one could learn everything (provided that man’s longevity gave him all the time necessary to experience everything.) The necessity of cause and effect stands at the crux of empirical philosophy, and while it is indeed a compelling argument, it can still be argued that if not all, then at least some knowledge is obtained outside of these means thus making it impossible to learn all things.
Much of the knowledge that empiricist argue is gained through cause and effect relies upon the latter of these two conditions. A very simple example is that of the wind; it is fair to say that a large proportion of the world is ignorant as to how it is caused, but can affirm its existence and claim to have knowledge of it. Yet it is also possible that a causeless and effect-less being or idea exists; an empiricist can argue in no way that tit does not exist since this being exists outside of the realm of perception (which is linked to cause and effect). In this way, it cannot be said that experience encompasses knowledge since knowledge should encompass all things.
Empiricism does very much to prove man’s perception and knowledge of the physical world, but does not adequately provide a means by which we may verify the existence of abstract ideas such as truth, beauty or justice. Whereas a rationalist would argue that ideas such as these are a priori, there appear to be no causal or sensory means that prove their existence.
This theory states that we do not know the world outside of information that the senses give us, that the senses act a intermediaries between ourselves and the world, and that the mind interprets the impressions that the senses leave upon it, continually categorising and reorganising them, if this is true, the it must also be so that it is impossible for us to truly know what we have experienced since the raw experience has been so modified by the mind, in this way, the empirical view can make it seem impossible to attain knowledge.
As with representative realism, this model of the theory of knowledge does not make ample provision for the possibility of illusory sensations. In Descartes’ Meditations, he poses the possibility that the each and every perception and piece of knowledge is part of a universal deception, even if this is not so, there are times when our own senses deceive us, such as when we believe we hear someone call our name in a noisy environment. If we take the traditional view that knowledge is justified true belief, then, since the very possibility that we are being deceived exists, we cannot accept that all knowledge is obtained from experience. This problem is worsened, as with sense data, in the fact that it is impossible to ensure that our senses give an accurate image of the world as it exists in reality.
Empiricism seems to do nothing more than explain what experiences are and how they contribute to our knowledge, but we cannot cite experiences as the sole basis of knowledge since (as said earlier) it can be proven that knowledge does not encompass all things. It is imperative that knowledge does necessitate all things since if there is even the minutest detail that could refute knowledge; the entire concept is flawed, much like Descartes’ concept of doubt and knowledge. One foreseeable way in which this is with the introduction of an absolute and flawless knowledge, which, no doubt, Descartes would say rests in God.
