When man discovered how to make fire to keep himself warm, his need of thought and effort was not ended; when he discovered how to fashion a bow and arrow, his need of thought and effort was not ended; when he discovered how to build a shelter out of stone, then out of brick, then out of glass and steel, his need of thought and effort was not ended; when he moved his life expectancy from nineteen to thirty to forty to sixty to seventy, his need of thought and effort was not ended; so long as he lives, his need of thought and effort is never ended.

Autor: Ayn Rand