Because of the central importance in Luther's thought of individual reading of the Bible, Protestantism encouraged literacy, not to mention printing, and these two things unquestionably encouraged economic development (the accumulation of ‘human capital') as well as scientific study. This proposition holds good not only in Prussia but also all over the world. Wherever Protestant missionaries went, they promoted literacy, with measurable long-term benefits to the societies they sought to educate; the same cannot be said of Catholic missionaries prior to Vatican II.