How does Descartes justify belief in an external material world? Is his justification convincing?
Descartes creates a focus on the external material world and his belief in it within his Sixth Meditation from Meditations of First Philosophy, although the basis of his ideas are constructed and explored within the earlier Meditations. Descartes justifies his belief in an external material world particularly through his reflections on the sensory impressions which the supposed external world imposes on him; but the concept of the Dream Argument which he explores within Meditation One somewhat hinder his justification. Additionally, Descartes’ belief in the external material world are heavily reliant on the existence of God, in particular to overcome the doubts of the Evil Demon Argument, to ensure that we are not being deceived and thus prove the existence of the outside world. Thus, Descartes justification of his belief in the external material world is adequately convincing, but there appears to be pitfalls in his argument which somewhat question its full integrity.
The Sixth Meditation opens with “the remaining task is to consider whether material things exist” (Descartes, 1641); at this point, Descartes has concluded the existence of God and himself, which creates the basis for his argument on the existence of the external material world. Without the prerequisites of the existence of himself and God, Descartes argument would ultimately fail, as will be later discussed; but Descartes forms a plausible argument throughout the Sixth Meditation which ultimately overcomes this.
The argument for his belief in the external physical world is anchored in the concept that we have sensory impressions of the world (Seminar 4 Notes, PPE First Year Seminar). From establishing his belief in the existence of himself as a ‘thinking thing’, Descartes notes that in addition to the images which he can form in his mind through his imagination, there are also other forms of ‘mental phenomena’ which originally led him to believe in the existence of his own body. The form of mental phenomena which are ‘mediated by the body’, such as heat, the colour and hardness of objects (Williams, 2005) are regarded as a reason for the belief in an external material world, since these sensations can be interpreted as the reactions of ‘sensory organs in relation to a material world.’ (Williams, 2005) In reality, this argument is incredibly convincing, particularly when you consider that your sensory impressions and experiences are involuntary and as a human being, you have no way to stop experiencing these. Even when we close our eyes, we are still seeing something, it is simply just the inside of our eyelids. This means that we never stop taking in information about this external material world. If these sensations were derived from something internal, such as our minds or imagination, we would have far more control over them since we have the mental power and capability to imagine, or ultimately not imagine, certain objects and thoughts.
However, our own senses are subject to misinterpretation which can ultimately be misleading. Within Meditation One, Descartes raises his own concern about the ambiguity between our states of waking and dreaming – “my inability to distinguish dreams from waking experience” (Descartes, 1641). Here Descartes outlines his Dream Argument, which explores how we have no guarantee at any given point in time that we are not dreaming when we believe that we are experiencing reality or the external material world. This argument, I believe, is realistically convincing and can be perceived by the reader in their own life. There is a strong likelihood that, on occasion, people have struggled to distinguish between reality and very vivid dreams, supporting this argument. On the other hand, for the most part we, as humans, have the ability to distinguish between dreams and reality based on clarity, since the information within dreams does not appear as clear and consistent as the information we receive from the ‘external material world’. This begins to diminish the doubts of the Dream Argument, but they are still ever-present and a valid counter to Descartes’ own arguments.
The notion of déjà vu also links into this doubt of Descartes, although he does not specifically reference it himself. The experience of déjà vu can feel incredibly disorientating and misleading, as though your own senses are deceiving you, which supports the idea that the senses are ultimately not always accurate. But, déjà vu is defined in the modern day as feeling of familiarity, which theoretically does not signify that it is your senses that are deceiving you, it may possibly just be a misconstrued thought process.
Additionally, within Meditation Six, Descartes considers phantom limb pain and its consequences on the credibility of the information which we receive from our senses. The implications of this highlight how our senses may deceive us, and our experiences of the outside world, not just on rare occasions but repeatedly. This evokes the question of how can we truly be sure that we are correctly experiencing and interpreting what our senses are telling us; what we currently believe to be the external material world may be not be true.
In spite of this, Descartes’ belief in God, which he established in the earlier chapters of his Meditations create a counter argument about the deception of our senses. There is the belief that God is benevolent, so he would not deceive us by putting these false perceptions into our head. The illusions and misconceptions which we experience in reality may not be due to God being a deceiver, but in fact unavoidable errors within the human body and mind. Problems can occur within the nerves and brains of humans which produce illusions that can mimic a realistic perception of the external material world. This is specifically the case with the aforementioned phantom limb pain, since the body is unaware that the limb is no longer there and sends information to the nerve endings. Although some may believe that God should not have created human beings in a way which made them susceptible to being misled and misinterpreting information from their own senses, it is not always possible to avoid problems with the brain and nervous system; injuries which occur throughout life may be the cause of these misinterpretations of the external material world, which means that God cannot be fully held to account for these errors (Elstein, 2018), especially if humans have the ability to exercise free will, thus their own actions may result in these injuries. This justification poses a convincing argument, especially in the modern day where medical and scientific studies can support the reasons behind certain phenomena outlined.
Throughout his Meditations, Descartes shows a strong inclination to believe that experiences are derived from the external material world, and this tendency is derived from the earlier mentioned concept of God not being a deceiver. If the thoughts which we experience regarding the supposed external material world were not true, and in fact originated from a higher being or power, albeit God or the Evil Demon (an argument mentioned by Descartes in Meditations), God would ultimately be a deceiver for making Descartes believe so strongly in the physical world (Williams, 2005). However, since God exists and is benevolent, and Descartes has earlier proved this, it shows that the external material world must exist because God would not deceive Descartes to such an extent where he believes so strongly in an idea which is in fact incorrect. Consequently, this argument could be problematically circular and just a method for Descartes to justify his own belief. Although I do not support this argument, since I too believe in the external material world, there is no guarantee that Descartes was completely understanding of God’s world at the time, so there may be some misconstrued ideas within his argument.
In conclusion, Descartes presents a convincing argument, which although it has its concerns, his justification ultimately prevails in my opinion. His focus on the sensory impressions that we take in from the world are the most poignant in my belief, and contribute most to his convincing justifications. Furthermore, the benevolence of God which he established in the earlier Meditations ultimately becomes the cornerstone of countering some of the possible rejections and criticisms of his argument; so without the proved existence and benevolence of God, his argument would fail. In addition, Descartes natural inclination to believe in the external material world highlights humans’ natural disposition to the physical world, and also points to the how we are not inclined to question our own physical existence, we somewhat take it for granted. Overall, I believe that Descartes sufficiently proves the existence of the external material world.
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Bibliography
Descartes, R. 1641. Meditations, trans. Bennett, J. at www.earlymoderntexts.com
Accessed 3rd November 2018
Elstein, D. 2018. Handout for Descartes’ Meditation 6. PHIL1111 PPE First Year Seminar
Newman, L. 2016. Descartes’ Epistemology. at https://plato.stanford.edu/entries/descartes-epistemology/. Metaphysics Research Lab, Stanford University. Accessed 2nd November 2018.
Williams, B. 2005. Descartes: The Project of Pure Enquiry. London: Routledge.