1735 eleventh edition. Three volumes bound in two. Large discolored area on rear board of second volume, a few spots on boards otherwise, evidence of repair along joints of both spines, corners a bit rubbed, a few pages lightly foxed, ink names on title page of each volume (C.J. Forbes, Florence; Tho. Storer). [xxxii], 372; [xvi], 340, [27] pp. 8vo. Contemporary full calf, black and red morocco spine labels, five raised spine bands, gilt titles and rules with decorations in compartments, speckled edges and marbled endpapers. First published in 1689, this is a foundational work in the influential British school of empiricism, of which Locke was among the leading proponents. Empirical philosophy argued that knowledge stemmed from subjective experience (a posteriori) rather than the operation of objective reason (a priori). As such, this work contains commentary on how the formation of ideas relates to sensation and perception. This edition includes an extensive index.