The image I choose the Blind Man, which is represented as a blindfolded man is being able to walk with sticks and see with his hands, takes place in Rene Descartes’ essay named La Dioptrique (‘On optics’). Since the blindfolded man sees with his hands, he does not need the help of his sleepy guide dog. This image has been seen firstly in Descartes’book Discours de la Methode in 1637. RenéDescartes (1596–1650) is a philosopher, mathematician and one of the major opticians of the seventeenth century. This essay aims to discuss and give place to the analysis of Descartes’ Blind Man image shown above. Briefly, first, I will be mentioning the subject of sticks being a medium that guides him namely make him see, then how this seeing process works like a natural process of seeing and the system of camera obscura since camera obscura is an optical tool to observe things. Following, the geometry from a perspective of Descartes, cartesian system and the positioning of sticks. Lastly, how blind man seeing with sticks similar to the natural seeing process, and where the brain stands at this discussion.
Descartes has doubts about the process of seeing, and this interrogation has been taken place in his essay La Dioptrique(‘On optics’) at 1637. At one point of his essay, Descartes invokes the hypothetical example of a blind man using a stick to help him navigate, proclaiming ‘one might almost say that they see with their hands’ (Paterson, 2016). Here, ‘seeing with their hands’ is the part that takes anyone’s attention; how is possible a literally blind man able to use sticks and being able to see things? Descartes mentions that the man habitually uses sticks as an extension of his senses. In order to make us understand the subject more easily, he gives examples from daily life: “It sometimes doubtless happened to you, while walking in the night without a light through places which are a little difficult, that it became necessary to use a stick in order to guide yourself;and you have then been able to notice that you felt, through the medium of the stick, the diverse objects around you and that you were even able to tell whether they were trees, or stones, or sand…” (Descartes, 2001) When we look at Descartes’ theory of visual-spatial perception; simple situation perception: “Our awareness of the direction in which our eye or head is turned enables us to determine where the object is located relative to our body, just as a blind man touching an object with a stick can tell what direction it lies in because he knows the direction in which his hand is turned.” Therefore, through the medium of the stick, a blindfolded human being is able to see as well.
Referring to the discussion of a blind man seeing through the medium of the stick, camera obscura can be likened to have a similar process of seeing, it is seen as a tool (optical device) which takes place in that seeing the process. It is like a projection of the outside world. A camera obscura in a fixed position is a tool that enables people to observe things. At this point, as French philosopherMerleau-Ponty (1908–1961), observes blind man’s stick has ceased to be an object, a tool for him, and is no longer perceived for itself; its point has become an area of sensitivity, extending the scope and active radius of touch (Ponty). It can be said that how camera obscura is a tool that a human use to observe things, the tool that the blind man uses to see is his sticks.
From another perspective, Descartes is a mathematician as well so it can be found out that he has established crucial relationships with geometry: CartesianCoordinate System which was found by René Descartes. Already, Descartes’s LaDioptrique of the blind man holding two crossed sticks seems to have beenenvisaging the Cartesian geometrization of vision (Tunstall, 2011). In the exploration of things, the Cartesian system is like a verification system which specifies each point in the universe and on x,y,z system. For the blind man case, holding two sticks AE, CE, whose length I suppose him not to know, and knowing [savoir] only the distance between his two hands A and C, and the size of the angles ACE and CAE, can from that, as though by a natural geometry, know [connaître] where E is (Wolf-Devine, 1993). One of the interesting things about the previous passage is Descartes’ “use of the verbs savoir andconnaître. The verb savoir (connoting an intellectual kind of knowledge) is used to describe the blind man’s knowledge of the distance between his hands and the angles made by the sticks, while connaître (meaning ‘to be acquainted with’) is used to describe his knowledge of where the point E is, as though he is trying through this use of the different verbs to arrive at the sort of directness and immediacy associated with the verb connaître, starting from intellectual and perhaps implicitly mathematical knowledge.” Additionally, Descartes refers to natural geometry only in his discussion of the blind man, whereas in the case of vision, he says that the length of the line and the size of the angles ‘make us know’ (connaître) where the point E is. (Wolf-Devine, 1993)
InLa Dioptrique, Descartes draws an analogy between the action of light on the eye and the movement of a blind man’s stick as it probes the surfaces of objects in its path and goes on to discuss the formation of images in the back of the eye (O’Riley, 1998). “A blind man with crossed sticks who is able to feel an object to the right with his left hand and one to the left with his right hand and a person who sees objects in their true situations ‘although the picture which they print in the eye has a wholly contrary situation’”. The blind man is not confused by the crossed sticks because he can direct his attention out from his hands. (Wolf-Devine, 1993) Briefly, when the blind man of whom it has spoken above touches some object with his sticks, the crossed sticks in the blindfolded man’s hands refer to the inversion of the retinal images. Descartes maintains that the man is still able to ‘perceive’objects in their correct relation (O’Riley, 1998). And, this is very much related with the process of seeing physically; in general, terms, so the rays from the object form an inverted image in the eye, then the image in the brain is reversed and the image is reversed, and visualization occurs.
Going back to geometry; there is axonometric projection is needed to be addressed related to the subject. Considering the perception of spatial depth, with the correct use of dimensions, angles, and distances the whole image can be produced. We do not see the object, but we know it is like this, we know the qualities of object. And, the understanding of perspective drawing: There is the illusion related from nature of the eye, our eyes cannot produce the exact image without brain, so it is like an illusion of eye. What we must do to grasp the image at this point is thinking and using our minds. Here, there is one thing that should be mentioned: René Descartes is regarded also as the father of modern philosophy for defining a starting point for existence, “I think; therefore I am.” (Editors, 2014) So, it might be said that blind man sees better than seeing man because he sees through his mind not eyes. We can see through our minds. It is in the mind, not the eye, that really “sees”.
Considering the point on the natural process of seeing, the mind needs to perceive certain images transmitted by the objects to the brain. And again, when we look at what Descartes argue on truth, mathematics, and visuality we seethe discussion of the ‘eye of the mind’ and the ‘eye of the body’. Thereis now a solution to this paradox, which is to distinguish between the”eye of the mind” and the “eye of the body” (Descartes1908, Rule V, p. 380). This “eye of the mind” sees more clearly. Going back to Descartes’ verb savoir (connoting an intellectual kind of knowledge), the “intellectual eye” sees all more clearly the more the body’s eyes remain blind.
In conclusion, as shown in the essay, the main point is to analyze the Blind Man image of Descartes by introducing of the ideas behind its creation. Respectively I have tried to mention the sticks the blind man holds, how they make him see as happened in the working system of camera obscura. Later, pointing out Descartes’ geometry, cartesian system, axonometric projection, and perspective projection accordingly the positioning of sticks. In the end, my purpose was to correlate the entire discussion to the brain. This is a process of seeing with the mind.
Descartes, R. (2001). Discourse on Method, Optics, Geometry, and Meteorology. (P. J. Olscamp, Çev.) Hackett Publishing.
Editors, B. (2014, April 1). The Biography.com website: https://www.biography.com/people/ren-descartes-37613
Krämer, S. (2012). The ‘eye of the mind’ and the ‘eye of the body’: Descartes and Leibniz on truth, mathematics, and visuality. In: Barth F.G., Giampieri-Deutsch P., Klein HD. (eds) Sensory Perception. Vienna.
O’Riley, T. (1998). Representing Illusions: space, narrative and the spectator. PhD, Chelsea College of Art & Design.
Paterson, M. (2016). Seeing with the Hands: Blindness, Vision and Touch After Descartes. Edinburgh University Press.
Ponty, M. (tarih yok). Phenomenology of Perception.
Tunstall, K. E. (2011). Blindness and Enlightenment: An Essay: With a new translation of Diderot’s ‘Letter on the Blind’ and La Mothe Le Vayer’s ‘Of a Man Born Blind’. Bloomsbury Publishing USA.
Wolf-Devine, C. (1993). Descartes’ theory of visual spatial. Southern Illinois University; 1st edition.