1 The Birth of Science - MSRI

54 3. Other Hellenistic Scientific Theories
tral perspective as codified in the fifteenth century, its existence in antiquity
is contested by many on the grounds that the Pompeii frescoes generally
seem to employ what is now called fishbone perspective (having
inconsistent vanishing points). There is dispute even about whether Euclid’s
Optics contains rules that have immediate application to the projection
techniques used in the Renaissance. The work certainly contains the
prerequisites of a theory of perspective, but, being about optics and not
scenography — that is, dealing with our sight of objects rather than with
the preparation of plane drawings that generate particular visual effects —
it does not develop this line of applications. Yet in spite of the complete
loss of all treatises on scenography, explicit applications of optics to central page 87
perspective are mentioned in surviving ancient works, 21 and are in fact evident
in some frescos, such as the one discovered in 1961 in the “House of
the Masks” on the Palatine Hill in Rome, which dates from around 30 B.C.
(see Figure ??). 21a Moreover central perspective is only one of the possible
applications of ancient optics; it is designed to optimize the visual impression
a painting makes when seen from a particular point, but it is not the
best technique in every case. 22 For instance, it is not well suited to big wall
paintings that will be looked at from many different positions. 23
Ancient optics and scenography had several other uses in the figurative
arts. Proclus writes:
Optics . . . uses visual rays and the angles they form; it is divided
into optics proper, which explains the appearance of objects at a distance,
including the convergence of parallel lines, . . . catoptrics, . . .
and scenography, which shows how, in images, what is seen might
be made not to appear out of proportion or deformed, according to
the distance and the heights of the things drawn. 24
21 Ptolemy (Geography, VII, vi–vii) provides instructions for drawing in perspective a world globe
with parallels and meridians (compare [Andersen]). An even more interesting example, noted by
A. Jones in a conference cited in [Knorr: PLP], is a passage in Pappus’ commentary on Euclid’s
Optics that deals with the vanishing point, identifying the point through which one should draw
the lines of a plane in order that they should appear parallel to a given line from a given point
of view (Pappus, Collectio, VI, prop. 51). Elsewhere in his commentary Pappus makes remarks on
linear perspective that are absent from Euclid’s Optics itself.
21a To be supplied
22 This was rightly stressed in [Panofsky]. In the same essay the author argued that Euclidean
optics led ancient painters to the use of a perspective distinct from, but not inferior to, the one
used in the Renaissance. Although the “angular perspective” he postulates is unconvincing, his
ideas may help explain features of certain works. It should be kept in mind, however, that he was
unaware of works such as the fresco in the House of Masks.
23 Even modern painters have often left aside central perspective in large murals, to void the
glaring deformations that would appear in peripheral areas to those not looking from the unique
“correct” viewpoint.
24 [Proclus/Friedlein], 40, 10–21.
Revision: 1.13 Date: 2002/10/16 19:04:00