The Development Hypothesis (1852)
“If a single cell, under appropriate conditions, becomes a man in the space of a few years, there can surely be no difficulty in understanding how, under appropriate conditions, a cell may, in the course of untold millions of years, give origin to the human race.”
Vol. I, Part III: The Evolution of Life, Ch. 3 : General Aspects of the Evolution Hypothesis; compare: "As nine months go to the shaping an infant ripe for his birth, / So many a million of ages have gone to the making of man", Alfred Lord Tennyson, Maud (1855)
Principles of Biology (1864)
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Herbert Spencer 81
English philosopher, biologist, sociologist, and prominent … 1820–1903Related quotes
Source: 1940s, Quasi-Stationary Social Equilibria and the Problem of Permanent Change, 1947, p. 40.
Vol. I, Ch. 1, Section 2, pg. 49.
(Buch I) (1867)
Source: A Theory of Justice (1971; 1975; 1999), Chapter III, Section 22, pg. 126
Source: As quoted in Medical research warning over human cells in animals https://www.theguardian.com/science/2011/jul/22/medical-research-humans-animals-regulation by Alok Jha, 22 July 2011, The Guardian.
Red Giants and White Dwarfs : Man's Descent from the Stars (1971), p. 249.
In operant conditioning we "strengthen" an operant in the sense of making a response more probable or, in actual fact, more frequent.
Science and Human Behavior (1953)
“You have an excellent heart, my friend — but your grey cells are in a deplorable condition.”
Hercule Poirot’s Early Cases (1974)