Can't process symbols predicationally or oppositionally
Chinese Room lacks understanding as it can't operate on the meanings of symbols—in particular it can't narrow down the meaning of an already meaningful symbol (predication), nor can it reason from what's the case to what's not the case (opposition).
All the Chinese Room can do is shuttle symbols around (mediation).
Note: For elaboration on these concepts, see the "Dialectical" arguments on Map 3.
Joseph Rychlak, 1991.