In his Fourth Book he so far departs from the doctrine implied in his chapters on the reality and adequacy of ideas and on the names of substances, as to treat the notion of several single subjects in which ideas co-exist (which he still holds to be the proper notion of substances), as a fiction of thought. There are no such single subjects. What we deem so are really ‘retainers to other parts of nature.’ ‘Their observable qualities, actions, and powers are owing to something without them; and there is not so complete and perfect a part that we know of nature, which does not owe the being it has, and the excellencies of it, to its neighbours’ (Book IV. chap. vi. sec. 11). As thus conceived of, the ‘objective order’ which our experience represents is doubtless other than that collection of fixed separate ‘things,’ implied in the language about substances which Locke found in vogue, but it remains an objective order still--an order of ‘qualities, actions, and powers’ which no multitude of sensible events could constitute, but apart from which no sensible event could have such significance as to render even a singular proposition of real truth possible. [1] See above, paragraph 117, sub. fin. Transition to doctrine of God and the soul. 126. It remains to inquire how, with Locke, the ideas of self and God escape subjection to those solvents of reality which, with more or less of consistency and consciousness, he applied to the conceptions on which the science of nature rests. Such an enquiry forms the natural transition to the next stage in the history of his philosophy. It was Berkeley’s practical interest in these ideas that held him back from a development of his master’s principles, in which he would have anticipated Hume, and finally brought him to attach that other meaning to the ‘new way of ideas’ faintly adumbrated in the later sections of his ‘Siris,’ which gives to Reason the functions that Locke had assigned to Sense. Thinking substance--source of the same ideas as outer substance.