Keen

Definitions: (1) acutely or finely perceptive; extremely sensitive, responsive, or alert; (2) having great acumen; shrewdly intelligent; penetratingly astute; (3) animated by strong feeling or desire; eager; interested; enthusiastic; (4) a recognition of delight; great; wonderful; marvelous

Quote: The whole idea of compassion is based on a keen awareness of the interdependence of all these living beings, which are all part of one another, and all involved in one another. — Thomas Merton (1915–1968) American Trappist monk

Observations:
• Men’s minds tend to fear more keenly those things that are absent. — Gaius Julius Caesar (100 BC–44 BC) Roman general & statesman
• It is hard to prevent oneself from believing what one so keenly desires. — Jean-Jacques Rousseau (1712–1778) Genevan philosopher