The function of the eye as explained by the camera obscura (70. 71).

70.

If the object in front of the eye sends its image to the eye, the
eye, on the other hand, sends its image to the object, and no
portion whatever of the object is lost in the images it throws off,
for any reason either in the eye or the object. Therefore we may
rather believe it to be the nature and potency of our luminous
atmosphere which absorbs the images of the objects existing in it,
than the nature of the objects, to send their images through the
air. If the object opposite to the eye were to send its image to the
eye, the eye would have to do the same to the object, whence it
might seem that these images were an emanation. But, if so, it would
be necessary [to admit] that every object became rapidly smaller;
because each object appears by its images in the surrounding
atmosphere. That is: the whole object in the whole atmosphere, and
in each part; and all the objects in the whole atmosphere and all of
them in each part; speaking of that atmosphere which is able to
contain in itself the straight and radiating lines of the images
projected by the objects. From this it seems necessary to admit that
it is in the nature of the atmosphere, which subsists between the
objects, and which attracts the images of things to itself like a
loadstone, being placed between them.

PROVE HOW ALL OBJECTS, PLACED IN ONE POSITION, ARE ALL EVERYWHERE
AND ALL IN EACH PART.

I say that if the front of a building--or any open piazza or
field--which is illuminated by the sun has a dwelling opposite to