What sort of person was the young naturalist who developed an evolutionary idea so logical, so dangerous, that it has dominated biological science for a century and a half? How did the quiet and shy Charles Darwin produce his theory of natural selection when many before him had started down the same path but failed? This book is the first to inquire into the range of influences and ideas, the mentors and rivals, and the formal and informal education that shaped Charles Darwin and prepared him for his remarkable career of scientific achievement. Keith Thomson concentrates on Darwin's early life as a schoolboy, a medical student at Edinburgh, a theology student at Cambridge, and a naturalist aboard the Beagle on its famous five-year voyage.Closely analyzing Darwin's Autobiography and scientific notebooks, the author draws a fully human portrait of Darwin for the first time: a vastly erudite and powerfully ambitious individual, self-absorbed but lacking self-confidence, hampered as much as helped by family, and sustained by a passion for philosophy and logic. Thomson's account of the birth and maturing of Darwin's brilliant theory is fascinating for the way it reveals both his genius as a scientist and the human foibles and weaknesses with which he mightily struggled.