In the Dark Ages, professional guilds kept tricks of the trade a secret so as to maximize member profits. Today, in contrast, the professional elite — in law, medicine or science — enrich society by sharing ideas and discoveries.

Attorneys C. Robert Zelinger and Carole W. Briggs, of Farmington, Conn.’s Levy & Droney, will each devote two weeks of their time next month going overseas to teach college classes.