This quote is commonly attributed to Leonardo da Vinci, but I have not been able to locate a primary source. Use with caution in academic or professional contexts.
“A man is worthy of praise or blame solely on account of those actions which lie within his power to do or not to do.”
— Leonardo da Vinci Primary source“Wisdom is the daughter of experience.”
— Leonardo da Vinci Primary source“Any one who in discussion relies upon authority uses, not his understanding, but rather his memory.”
— Leonardo da Vinci Primary source“Just as iron rusts unless it is used, and water putrifies or, in cold, turns to ice, so our intellect spoils unless it is kept in use.”
— Leonardo da Vinci Primary sourceMore quotes by Leonardo da Vinci →
“Knowledge is of no real value if all you can tell me is what happened yesterday. It is necessary to tell what will happen tomorrow.”
— Richard Feynman Primary source“Wish not so much to live long as to live well.”
— Benjamin Franklin Primary source“A long life may not be good enough, but a good life is long enough.”
— Benjamin Franklin Primary source“All would live long, but none would be old.”
— Benjamin Franklin Primary source