“Optimism is the one quality more associated with success and happiness than
any other.”
“I do not think that there is any other quality so essential to success of any kind as the quality of perseverance.”
As quoted in How They Succeeded (1901) by Orison Swett Marden
Context: I do not think that there is any other quality so essential to success of any kind as the quality of perseverance. It overcomes almost everything, even nature.
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John D. Rockefeller 29
American business magnate and philanthropist 1839–1937Related quotes

http://www.insidehighered.com/views/2013/10/17/liberal-arts-are-best-preparation-even-business-career-essay

Source: Father and Child Reunion (2001), p. 30.

1900s, Address at the Prize Day Exercises at Groton School (1904)
“It is the deep, salty stickiness of food that intrigues me more than any other quality.”
The Guardian, London, Not roquette science, 2005-10-29, 2010-05-20 http://books.guardian.co.uk/reviews/houseandgarden/0,,1602953,00.html,

1860s, Our Composite Nationality (1869)
Context: The theory that each race of men has some special faculty, some peculiar gift or quality of mind or heart, needed to the perfection and happiness of the whole is a broad and beneficent theory, and, besides its beneficence, has, in its support, the voice of experience. Nobody doubts this theory when applied to animals or plants, and no one can show that it is not equally true when applied to races. All great qualities are never found in any one man or in any one race. The whole of humanity, like the whole of everything else, is ever greater than a part. Men only know themselves by knowing others, and contact is essential to this knowledge. In one race we perceive the predominance of imagination; in another, like the Chinese, we remark its almost total absence. In one people we have the reasoning faculty; in another the genius for music; in another exists courage, in another great physical vigor, and so on through the whole list of human qualities. All are needed to temper, modify, round and complete the whole man and the whole nation.