One friend in a lifetime ismuch; two are many; three are hardly possible.Friendship needs a certainparallelism of life, a community of thought, a rivalry of aim.

-Adams, Henry Brooks
  The Education of Henry  Adams, ch.20.

Man is essentially the imitative animal. His whole educabilityand in fact the whole history of civilization depend on this trait, which his strong tendencies to rivalry, jealousy, and acquisitiveness reinforce.

-James,William
  The Principles of Psychology, ch.24.

Here, of all her cities, throbbed the true lifeöthe true power and spirit of America; gigantic, crude with the crudityof youth, disdaining rivalry; saneand healthyand vigorous; brutal in its ambition, arrogant in the new- found knowledge of its giant strength, prodigal of its wealth, infinite in its desires.

-Norris, Frank Benjamin Franklin
  Of Chicago. The Pit, ch.2.