Norman Vincent Peale Quotes about Perseverance

Problems are to the mind what exercise is to the muscles, they toughen and make strong.
Dr. Norman Vincent Peale (2007). “The Tough-Minded Optimist”, p.174, Simon and Schuster
Dr. Norman Vincent Peale (2007). “The Tough-Minded Optimist”, p.13, Simon and Schuster
Norman Vincent Peale “The Power of Positive Thinking”, Om Books International