Light is the name of the shadow of the living light.
I still remember my astonishment, ten years ago, when I saw video screens replacing mirrors on Paris Metro platforms.
Soon after 1968, it is true, surveillance cameras had appeared at the entrances to the grandes écoles and universities, and this new equipment was also used to keep watch on the boulevards and major junctions of the capital.1 Today, I am astonished once again when I see the lens of a micro-camera rising above the keypad that gives coded access to a block of flats. Evidently entry phones are no longer enough to do the job of the old concierges.
As an electro-optical substitute, videoscopy seems to come into its own with this ...