Definitions: (1) having court-like manners; thoughtful of others; polite and gracious; (2) at minimum actively considerate and sometimes stately politeness

Synonyms: affable, attentive, civil,  comity, conciliating, obliging, respectful

• He who sows courtesy reaps friendship.— Saint Basil (329-379) Bishop of Cappadocia
• One of the most graceful of warriors is the robin. I know few prettier sights than two males challenging and curveting about each other upon the grass in early spring. Their attentions to each other are so courteous and restrained. — John Burroughs (1837–1921) American naturalist

Consideration: Common courtesy is the backbone of civilization. Simple consideration of others could easily be the foundation of a new world order.

Fictional Figure: Sir Calidore, a knight who typifies courtesy — Edmund Spenser (1552-1599) English poet, The Faërie Queene {1590}

Legendary Figure: Sir Gawain, King Arthur’s nephew, famous for strength and courtesy