Self-Portrait by Ernst Mach (1886)

Automated excerpt

If I close my right eye, the picture represented in the accompanying cut is presented to my left eye. If I observe an element A within my field of vision, and investigate its connexion with another element B within the same field, I step out of the domain of physics into that of physiology or psychology, provided B, to use the apposite expression of a friend of mine made upon seeing this drawing, passes through my skin. L" in question is Mach's colleague at Prague University, Prof.

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