Thoughts cannot be held by steel nor by concrete walls. M
(Our spirit cannot be caught!)
There is a fine line we walk between unstable illusions and concrete illnesses, falling to either side in sheer blindness.
When a Lion wants to meet with his subordinates, patience becomes the order of the day and not because he is the king of the jungle but because his words are concrete.
We thus make a fundamental distinction between the competence (the speaker-hearer's knowledge of his language) and performance (the actual use of language in concrete situations).
(Noam Chomsky (b. 1928), U.S. mathematical linguist, philosopher, psychologist, political critic. Aspects of the Theory of Syntax, p. 3 (1965).
Drawing the author's key distinction for dismissing raw empirical data as providing direct counter-evidence to his linguistic theories of grammar.)