From Bart Schulz’s outstanding SEP entry on Henry Sidgwick:
Sidgwick’s versatile and many-sided intellect—not to mention his keen wit—are typically better displayed in his essays and letters than in his best-known academic books. He was in fact much loved for his gentle humor (or “Sidgwickedness”) and sympathetic conversation, and his philosophical students prized him for his condor.
Will Wilkinson 