visive faculty be obtained by mortals. In the meantime, I propose it to
the consideration of the ingenious, whether the LOCUS APPARENS of an
object placed as in this 9th section be not as much before the eye as the
distinct base is behind the eye!' To which query we may venture to answer
in the negative. For in the present case the rule for determining the
distance of the distinct base, or respective focus from the glass, is this:
as the difference between the distance of the object and focus is to the
focus or focal length, so the distance of the object from the glass is to
the distance of the respective focus or distinct base from the glass.
[Molyneux Dioptr., Par. I. Prop. 5.] Let us now suppose the object to be
placed at the distance of the focal length, and one half of the focal
length from the glass, and the eye close to the glass, hence it will follow
by the rule that the distance of the distinct base behind the eye is double
the true distance of the object before the eye. If therefore Mr. Molyneux's
conjecture held good, it would follow that the eye should see the object
twice as far off as it really is; and in other cases at three or four times
its due distance, or more. But this manifestly contradicts experience, the
object never appearing, at farthest, beyond its due distance. Whatever,
therefore, is built on this supposition (VID. COROL. I. PROP. 57, IBID.)
comes to the ground along with it.

41. From what hath been premised it is a manifest consequence that a man
born blind, being made to see, would, at first, have no idea of distance
by sight; the sun and stars, the remotest objects as well as the nearer,
would all seem to be in his eye, or rather in his mind. The objects
intromitted by sight would seem to him (as in truth they are) no other
than a new set of thoughts or sensations, each whereof is as near to him
as the perceptions of pain or pleasure, or the most inward passions of
his soul. For our judging objects provided by sight to be at any
distance, or without the mind, is (VID. sect. 28) entirely the effect of