Crossword-Solution: SUBTILISATION 13 letters, 1 clue 🏆 scrabble score: 15

Still, in all this erroneous subtilisation, and these abortive efforts, Kant perceived a grasping at some real idea--fugitive indeed and coy, which had for the present absolutely escaped; but he caught glimpses of it continually in the rear; he felt its necessity to any account of the human understanding that could be satisfactory to one who had meditated on Locke's theory as probed and searched by Leibnitz.

Hence the soundness of Wagner's advice to the modern composer--Do not consciously aim at harmonic and instrumental effects, but wait till there is a sufficient cause for them.[393] His own practice was a model of restraint: not one modulation, not one subtilisation of the harmony, not one addition to the orchestral weight without a thoroughly good reason, rooted in the nature of the idea itself.