The taking-into-account 
theory of constancy, by 
contrast, implies mental 
computation. To infer that an 
image whose visual angle is 
small but whose source is far 
away represents a large object 
is a process somewhat like 
thought. It would require 
knowledge, albeit 
unconsciously represented, of 
how visual angle depends upon 
distance. Thus, perception for 
this kind of theory depends 
upon a much greater, active 
role of the mind. In that 
respect, the theory can be said 
to have its roots in a very 
different tradition of 
philosophy. Perception would 
thus be much more the result of 
mental reconstruction than of 
a passive monitoring of 
stimulation or of spontaneous 
neural interaction.