The biographer does not trust his witnesses, living or dead. He may drip with the milk of human kindness, believe everything that his wife and his friends and his children tell him, enjoy his neighbors and embrace the universe — but in the workshop he must be as ruthless as a board meeting smelling out embezzlement, as suspicious as a secret agent riding the Simplon-Orient Express, as cold-eyed as a pawnbroker viewing a leaky concertina. With no respect for human dignity, he plays off his witnesses one against the other, snoops for additional information to confront them with, probes their prejudices and their pride, checks their reliability against their self-interest, thinks the worst until he is permitted to think better.

Paul Murray Kendall
Paul Murray Kendall (1911-1973) American academic and historian
“Walking the Boundaries,” The Art of Biography (1965)
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