Are abstract concepts maintained as pure abstractions, or are they scaffolded by more concrete, perceptually-available concepts? In this dissertation, I present three empirical papers which use two test beds, time and number, to explore the cognitive and neural basis of abstract concepts and their relationship to basic sensory and perceptual processes. In the case of time, imperceptible duration piggybacks on representations of perceptible spatial extent. In the case of number, a seemingly abstract mathematical property is rapidly extracted as a basic perceptual feature by the visual system (presumably, a similar process may take place in other primary sensory tissues). The intraparietal sulcus, long implicated in numerical cognition, appears not to be the origin of number representations, but rather a hub where numerical inputs from sensory cortex may become more abstract number concepts. These studies support an account of concepts in which "abstract" conceptual thought is rooted in, and relies upon, basic sensory and perceptual mechanisms.