Via my doctoral student (and Newsgames co-author) Simon Ferrari, this snippet from Lev Vygotsky's classic text Mind in Society:

A special feature of human perception—which arises at a very young age—is the perception of real objects. This is something for which there is no analogy in animal perception. By this term I mean that I do not see the world simply in color and shape but also as a world with sense and meaning. I do not merely see something round and black with two hands; I see a clock and I can distinguish one hand from the other. Some brain-injured patients say, when they see a clock, that they are seeing something round and white with two thin steel strips, but they do not know that it is a clock; such people have lost their real relationship with objects. These observations suggest that all human perception consists of categorized rather than isolated perceptions.