Perspective Defined: Painting and the Pyramids of Sight
Four successive attempts to define perspective as the demonstrative reason of the eye's pyramids
An entirely textual folio in which Leonardo works, through several cancelled drafts, toward a single definition of perspective. He begins by asserting that painting is founded on perspective, which represents the office of the eye in gathering the forms and colours of objects by pyramids of lines. Successive reformulations call perspective a "demonstrative reason" showing how objects send their images to the eye along pyramidal lines that start from the edges of each body and converge to a single point. The final, numbered version synthesizes these: experience confirms that all things send their images to the eye by pyramidal lines, that equal bodies subtend larger or smaller pyramidal angles according to distance, and that the point receiving all the pyramids' tips is indivisible.
On this page
Painting is founded upon perspective; the office of the eye
Painting is founded upon perspective, which is knowing how to represent the office of the eye: the taking, by pyramids, of the forms and colours of all objects before it. No thing is so small that it is not larger than the place in the eye to which the pyramids are led, so the lines drawn from a body's edges to a single point must be pyramidal.
Perspective as demonstrative reason and pyramidal lines
Perspective is nothing but demonstrative reason, considering how objects before the eye send it their images by pyramidal lines. Pyramids are the lines that start from the superficial edges of each body and converge, through distance, to a single point.
A further draft of the definition
A further attempt, heavily worked over: perspective is demonstrative reason by which one effectually comprehends how objects send their own images to the eye by pyramidal lines. Several broken phrases show Leonardo searching for the right formulation.
The final definition: pyramidal lines and the indivisible point
Perspective is the demonstrative reason by which experience confirms that all things send their images to the eye by pyramidal lines; bodies of equal size subtend a greater or lesser angle according to distance. A point is that which cannot be divided into parts, and the point in the eye receives all the tips of the pyramids into itself.