The term 'knowledge work' appeared in The Landmarks of Tomorrow (1959) by Peter Drucker.[12] Drucker later coined the term 'knowledge worker' in The Effective Executive[13] in 1966. Later, in 1999, he suggested that "the most valuable asset of a 21st-century institution, whether business or non-business, will be its knowledge workers and their productivity."

Humboldt was an environmental scientist even before the words environment or ecology were coined (1827 and 1875, respectively).