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Norman Vincent Peale: People become really quite remarkable when they start thinking that they can do…

People become really quite remarkable when they start thinking that they can do things. When they believe in themselves they have the first secret of success.
Norman Vincent PealeSourced
Source
From the book You Can If You Think You Can, The first sentence is in the scanned 1976 printing; the two-sentence form is dated April 13 in Positive Thinking Every Day (1993) per Wikiquote

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