Bk.1 Letter #    ( Bk.XIII Let # ):   Bk.1 Page #      Writer to Receiver          Place, Date                            Remarks     EL:L01 (0 1 ) :275        Oldenburg to Spinoza   London,16/26 Aug.1661        Bk.I :275 1,2 — EL:[20] : xvi 1 .  Oldenburg after complimenting Spinoza, asks him  to enter into a