Thomas Henry Huxley (; 4 May 1825 – 29 June 1895) was an English biologist specialising in comparative anatomy. He is known as "Darwin's Bulldog" for his advocacy of Charles Darwin's theory of evolution.
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There is a well-worn adage that those who set out upon a great enterprise would do well to count the cost. I am not sure that this is always true. I think that some of the very greatest enterprises in this world have been carried out successfully simply because the people who undertook them did not count the cost; and I am much of the opinion that . . . the most instructive consideration for us is the cost of doing nothing.