The text discusses how the rays from the furthest points of objects intersect before entering the eye, akin to a camera obscura setup. It emphasizes the importance of understanding how perceived images are transmitted through the optic nerves to the brain. The explanation includes details on how light forms images accurately and why further study of visual perception is needed.
Actual Sensations
Entering the eye: because the rays that come from the furthest points of objects must necessarily intersect before entering the eye; if it were not possible, they would not be able to penetrate the eye. This is similar to the setup of a camera obscura, where external illuminated bodies are projected through a small hole onto a white paper, cloth, or wall; and as you can clearly see in the first example of the thesis sketch. There is no doubt that in such a representation, the rays of light from the tower A.B. can only be directed through the opening D. to form the points of that object at E.F., as it is shown here; inserting that the crossing of the rays at D. causes the top point A. to pass into E., and the base B. into F., so that the tower, whatever its position or context, is formed by the light, cannot be displayed in an inverted state.
The manner in which objects, that can only enter our eyes incorrectly, are perceived and judged by us in their proper form deserves further investigation, and we do not intend to neglect making this clear. One must again assume that the images of objects are not only painted or formed on the foundation of the eye, where they remain, but also that they are transmitted from there through the optic nerves into the brain under the action of movement; these nerves proceed with countless threads or vessels, over the visual area.
Translation Notes:
The term "Vertoog-Schets (S.)" refers to an example or diagram discussed in the text.
"Gesigt-Zenuwen" has been translated as "optic nerves," referring to the nerve bundles transmitting signals from the eye to the brain.