Jean-Jacques Rousseau, Gustave Le Bon, Sigmund Freud, Charles Mackay, Wilfred Trotter, Everett Dean Martin, Walter Lippmann, Gerald Stanley Lee & William McDougall
Charles Mackay, Jean-Jacques Rousseau, Gerald Stanley Lee, Gustave Le Bon, Walter Lippmann, William McDougall, Everett Dean Martin, Wilfred Trotter, James Strachey, G. D. H. Cole & Sigmundo Freud