Law of the instrument

The law of the instrument, law of the hammer, Maslow's hammer, or golden hammer is a cognitive bias that involves an over-reliance on a familiar tool. Abraham Maslow wrote in 1966, "If the only tool you have is a hammer, it is tempting to treat everything as if it were a nail."

The concept is attributed both to Maslow and to Abraham Kaplan, although the hammer and nail line may not be original to either of them.