Example Of Article Review On Descartes: Optics

On his discourse on light, Descartes acknowledges that our life experiences are dependent on our senses. With sight being at the center of man’s understanding of the world, Descartes attacks the accuracy of people’s perception. He provides a compelling argument about inaccuracy of human sensory perception through comparison of blind man and normal man’s perception of the surroundings.
Descartes opens the discussion by describing the experience of walking with a stick, which is used to explore the sensations of the surrounding environment. He compares the interaction of the stick, the object, and the hand in a blind man with the interaction of the light, the object and the eye in a normal man. With this argument, Descartes asserts that light rays are the objects through which normal man interacts with objects just like a blind man uses the stick to interact with objects.
In addition, Descartes uses the wine-vat example to explain the existence of light rays. In this example, he invites the reader to imagine a wine-vat full of half-pressed grapes with two holes at the bottom. Further, he asserts that a subtle and fluid matter that flows from the “heavenly bodies” fills the pores of objects in the world. He compares the fluid matter with wine, and the less fluid matter such as the transparent bodies with the half-pressed grapes.
When the wine-vat is opened, the grapes bunches move down as the wine flows out of the holes, even though the grapes cannot pass through the holes. In the same way, the light from objects passes through the air and transparent objects to reach the eyes of man, without the object moving in any way. Descartes asserts that light from objects is should not be viewed as a movement of the object but rather an action of the object and the light rays are the paths through which the light in objects moves.
According to above example, light is always in motion. Therefore, the laws of movement should apply to light, just as they would apply to an object such as a ball in motion. This third example by Descartes illustrates how light can be stopped, reflected, or refracted by objects it comes into contact. The interaction of light with the bodies of different color reflects the light differently, and others, such as black bodies, do not reflect the light at all.
In conclusion, the article argues that the body acts as a system through which the soul interacts with the external environment. The nervous system is at the center of the transmission system, fetching ideas, images, and feelings from the external environment, and relaying them to the soul or brain, which then interprets them accordingly. Consequently, a man will perceive the environment as an interaction between the environment and the nervous system. In the case of sight, it is the interaction between the light, from luminous or illuminated objects and the eyes.