Molyneux, William (1656-1698)

Dioptrica Nova, A Treatise of Dioptricks in Two Parts

London

Printed for Benj. Tooke

1692

"[T]he Explanation whereof is allowed by all men as satisfactory, 'tis this, in Tab. 41. Fig. 2. the Image a b of the Object A B is painted on the Retina inverted, and yet the Eye (or rather the Soul by means of the Eye) sees the Object erect and in its natural Posture."

And that the Concurrence of the Axes Optici in a single Point or Object is sufficient to make that Object seem but one besides the Proof of the foregoing Experiments, I shall endeavour to evince, or at least to explicate, by an other known Affection of Vision; the Explanation whereof is allowed by all men as satisfactory, 'tis this, in Tab. 41. Fig. 2. the Image a b of the Object A B is painted on the Retina inverted, and yet the Eye (or rather the Soul by means of the Eye) sees the Object erect and in its natural Posture; Because the Mind takes no notice of what happens to the Rays in the Eye by Refraction or Decussation, but in its direction towards the Object; it follows streight alongst the Rays as they by their Impulse and in their plain Course lead it, and consequently following the Rays a A, it is directed strait to the upper part of the Object; and also following the Rays b B, it is directed to the lower part of the Object, and so of the rest: for suppose the Ball of the Eye taken out of its Socket, or Cavity in the Skull, and a Man receives in the Socket an impulse by a Stick coming in the posture of B b, and hitting him on the upper part of the Cavity, surely he would never look for the Original of this Blow at A, but would be certainly directed to hunt back as it were alongst the Stick b B towards the Place from whence the Stroak comes. So the mind does hunt back by means of each Pencil of Rays (which are as it were a Stick giving the Retina a certain Impulse) to the Point from whence it comes, and is thereby directed strait thereto. To apply this to what I intend, I say then, that the Mind or visive Faculty (if I may have leave to use that Word for a thing we all understand and cannot better express) takes no notice that there are two Axes Optici, or two Pictures made by those Axes Optici on each Retina, but following back, and hunting counter alongst these Axes, it is directed to, and determined in one single Point, and therefore it sees it as one.
(pp. 289-90)

Visual Arts::Painting Body::Eye Optics::Image

Reading

William Molyneux, Dioptrica Nova, A treatise of Dioptricks in Two Parts: Wherein the Various Effects and Appearances of Spherick Glasses, both Convex and Concave, Single and Combined, in Telescopes and Microscopes, Together with their Usefulness in Many Concerns of Humane Life, are Explained (London: Benjamin Tooke, 1692).

Reading a copy at the Folger Library, text from EEBO-TCP <Link>

05/15/2013