One of the symptoms of an approaching nervous breakdown is the belief that one's work is terribly important.
- Bertrand Russell (1872-1970)
Moral indignation is jealousy with a halo.
- H. G. Wells (1866-1946)

The first zoo in the United States was Philadelphia Zoo. It is renowned for innovation in animal care and an unwavering commitment to wildlife. A zoo of firsts, Philadelphia Zoo has been a leader since opening its historic gates on July 1st, 1874.