“Once the tautology ‘the world is described by descriptive concepts’ is freed from the idea that the business of all non-logical concepts is to describe, the way is clear to an ungrudging recognition that many expressions which empiricists have relegated to second-class citizenship in discourse are not inferior, they’re just different."
Descriptive concepts are not the only kinds of concepts. There is a temptation of empiricists in assimilating all expressions to descriptive expressions (such that anything not intelligible as descriptive is defective).
The negation of this is called decriptivism.
The Tractatus was supremely descriptivist, yet made a key advance by noting that logical expressions play a different kind of role (prior to Tractatus, Russell would be looking into the world to try to see what distinguishes positive from negative facts, when he should not have been looking to the world).
Sellars extends this even further. The later Wittgenstein saw language as playing an unsurveyable variety of roles.
Most interesting philosophical concepts come with a “-ing” “-ed” distinction that’s crucial. Is a justification an act of justifying vs what’s justified (related Agrippean trilemma). Is an experience an act of experiencing vs what’s experienced.