In an old Zen sto­ry, two monks argue over whether a flag is wav­ing or whether it’s the wind that waves. Their teacher strikes them both dumb, say­ing, “It is your mind that moves.” The cen­­turies-old koan illus­trates a point Zen mas­ters — and lat­er philoso­phers, psy­chol­o­gists, and neu­ro­sci­en­tists — have all empha­sized at one … Con­tin­ue read­ing Why Most Ancient Civ­i­liza­tions Had No Word for the Col­or Blue