Full Idea
Sellars' Grain Problem contended that it was a problem for materialism that physical objects have a granularity whereas sensations are homogeneous and without grain.
Gist of Idea
The 'grain problem' says physical objects are granular, where sensations appear not to be
Source
report of Wilfrid Sellars (Empiricism and the Philosophy of Mind [1956], Ch. n22) by Thomas W. Polger - Natural Minds Ch.1 n22
Book Reference
Polger,Thomas W.: 'Natural Minds' [MIT 2004], p.250
A Reaction
This doesn't strike me as a serious problem. I assume that my sensations are granular, but at a level too fine for me to introspect. There are three hundred trillion connections in the brain (Idea 2952), a lot of them involved in sensations.
Related Idea
Idea 2952 A 1988 estimate gave the brain 3 x 10-to-the-14 synaptic junctions [Lockwood]