He accepts the scriptures as a secondary light, saying that they may not be esteemed the "principal ground of all Truth and Knowledge, nor yet the adequate primary rule of faith and manners," that they cannot go before the teaching of the very spirit that makes them intelligible. He maintains that the closing adjuration in the Book of Revelation refers only to that particular prophecy, and is not intended to suggest that prophecy is at an end. The ground of knowledge is immediate revelation, which may not be "subjected to the examination either of the outward Testimony of the Scripture or of the Natural Reason of Man as to a more noble or certain Rule or Touchstone." He considers that Augustine's doctrine of original sin was called out by his zeal against the Pelagian exaltation of the natural light of reason. He admits that man in sin--the natural man--can know no right; that, therefore, the Socinians and Pelagians are convicted in exalting a "natural light," but that, nevertheless, God in love gives universal light, convicting of sin, and teaching if not resisted. He qualifies the Quaker claim to the possibility of absolute present salvation from sin by adding that there may be a falling off. The whole of his argument displays the impossibility of rationalizing the position to which the Quakers had felt their way in terms of the absolute dualism of seventeenth-century philosophy. He places the doctrines of natural sinfulness and of universal light side by side, and so leaves them. The logical instability of Quaker formulas due to the limitations of the scientific philosophy of the day (not until the dawn of our own century has a claim analogous to theirs been put forward on the intellectual plane)--due, in other words, to the characteristic lagging of thought behind life, while comparatively immaterial in the founders and leaders of the Quaker movement, who were all mystics or mystically minded persons, a variation of humanity, peculiar people gathered together, with all their differences, by a common characteristic, seeing their universe in the same terms urged towards unanimous activity--began to bear fruit in the second generation. Mystical genius is not hereditary, and to the comparatively imitative mass making up the later generations the Inward Light becomes a doctrine, a conception as mechanical and static as is the infallible Scripture to the imitative mass of the Protestants.