One interlocutor writes about non-human animals:
"[they] recognize and remember certain objects, shapes, predators, etc., and know how to respond. But none of this requires or involves the apprehension of common natures of things, which would require a categorial jump from sensed particulars to general ideas that involve no residue of sensible matter, as do images generated by the memory and imagination in the brain."
It's difficult for us to say what animals experience when they assimilate sensory impressions. Nonetheless, the human apprehension and neural representation of sensate elements is not exactly analogous to the process whereby animals sense things and remember them. The human brain is capable of representing images in a way that differs markedly from cats or dogs. What makes our representations so different? We form concepts by means of natural languages and information derived from distal and proximal stimuli. Furthermore, while I believe that we form concepts by means of sensory experience in the way I've outlined, I don't necessarily buy into the "common natures" assumption. Concept-formation can be explained without appealing to non-physical factors like Platonic/Aristotelian Forms or immaterial souls.
But I am not arguing that perceptions are conceptions. What I am suggesting is that conceptions are possible representations of percepts by dint of natural language and neural networks in the human brain. George Lakoff and Mark Johnson (based on the work of Eleanor Rosch) have argued that we categorize things (e.g., birds, chairs, tables, and teapots) according to fuzzy prototypical characteristics (cf. Metaphors We Live By). However, the prototypes by means of which we classify various objects emanate from somatic experiences. For example, although I had never seen a Highland Cow until the year 2002, I knew that it was a cow upon first sight. Yet the Highland Cow was unlike any cow I had ever seen before. Lakoff and Johnson might say that I was able to associate the Scottish cow with my prototype of such animals based on past somatic experiences. Yet my concept of cowness is nothing more than the result of what I've perceived with my sense organs (inter alia) and how my brain represents the usual properties of cows which it derives from distal and proximal stimuli.