Abstraction still holds its feet on the ground.

In view of current scientific knowledge, it seems premature to hypothesize a qualitative distinction between processes, networks, and structures involved in abstract processes from those based on perception, episodic, or procedural memories. Predictive thought and mental travel strongly rely, at different levels of consciousness, on past and ongoing sensory input, bodily information (e.g., interoception), and the results of perceptual elaboration.