The fact that the face of a friend looks the same whether you are viewing it from directly in front or from the side is best accounted for by:

Question

Quizplus · Accepted Answer

The phenomenon described in the question is an example of shape constancy. This is the ability of our brain to perceive the shape of an object as constant, even when viewed at different angles or in different lighting conditions. In the case of a friend's face, our brain is able to recognize the features and overall shape of the face despite changes in perspective, allowing us to easily identify the person whether we are viewing them from the front or side.

The Fact That the Face of a Friend Looks the Same