DRAWING AND PERCEPTUAL 
CONSTANCY 

To make a representational 
drawing of a three-dimensional 
object or scene, we must draw a 
picture that will give the 
observer a retinal image similar 
to the one obtained in viewing 
the object or scene itself. But 
we do not directly perceive our 
retinal images. Instead, we 
spontaneously perceive a world 
of objects and planes that 
departs considerably from the 
size and shape relations given 
within the image. Thus, if we 
draw what we perceive, we will 
not draw in perspective.

    The major difficulty in 
drawing--at least in drawing by 
copying from the scene--is that 
we are foiled by the 
achievements of our 
perceptions, which accord so 
well with the actual 
characteristics of objects 
instead of with the 
characteristics of the 
stimulation reaching the eye. 
This is particularly noticeable 
in the art of children. If 
children are asked to copy a 
table while standing at one end 
of it, they tend frequently to 
draw what they perceive: a 
rectangular surface the far end 
of which is equal to the near 
end, with nonconverging sides 
and length not foreshortened. 
Plates on the table are likely to 
be drawn as circles, not 
ellipses.