In these days of advanced thinking it is a matter of common observation that we have left many of the old landmarks behind and that we are now pressing forward to greater heights and to a wider horizon than that which represented the mind-content of our progenitors. It has been suggested that human progress moves in cycles, and that we are continually reverting to the state of affairs and the theoretical outlook upon life that held the minds of former generations. The further suggestion is that we do not trace the same circle on the same plane, but that each successive return to our former condition finds us somewhat higher in the scale of civilisation and mental development...