Subtlety, sharpness, and biting quality

Meaning

Internal subtlety and acuité describe the spirit’s penetrating, upward-tending power. Sharpness is an efficacy word here, not merely the geometry of an edge. The Saturn interpretation later gives a related biting quality, mordante poncticité, to the devouring action figured by his scythe.

The two uses connect action and sensory language without identifying a particular modern acid or reagent. The protected spelling poncticité should remain visible rather than be silently replaced with a conjectured technical term. Neither the description of biting power nor its association with a mythic tool is advice to test a material by taste or contact.