I will remind you in conclusion, that our argument for the existence of God is at present incomplete. I have tried to lead you to the idea that the ultimate Reality is spiritual, that it is a Mind which knows, or is conscious of, matter. I have tried to lead you with the Idealist to think of the physical Universe as having no existence except in the mind of God, or at all events (for those who fail to follow the idealistic line of thought) to believe that the Universe does not exist without such a Mind. What further relation exists between physical nature and this Universal Spirit, I shall hope in the next lecture {27} to consider; and in so doing to suggest a line of argument which will independently lead to the same result, and which does not necessarily presuppose the acceptance of the idealistic creed. LITERATURE The reader who wishes to have the idealistic argument sketched in the foregoing chapter developed more fully should read Berkeley's _Principles of Human Knowledge_. For the correction of Berkeley's sensationalistic mistakes the best course is to read Kant's _Critique of Pure Reason_ or the shorter _Prolegomena to any future Metaphysic_ or any of the numerous expositions or commentaries upon Kant. (One of the best is the 'Reproduction' prefixed to Dr. Hutchison Stirling's _Text-book to Kant_.) The non-metaphysical reader should, however, be informed that Kant is very hard reading, and is scarcely intelligible without some slight knowledge of the previous history of Philosophy, especially of Locke, Berkeley, and Hume, while some acquaintance with elementary Logic is also desirable. He will find the argument for non-sensationalistic Idealism re-stated in a post-Kantian but much easier form in Ferrier's _Institutes of Metaphysic_. The argument for a theistic Idealism is powerfully stated (though it is not easy reading) in the late Prof. T. H. Green's _Prolegomena to Ethics_, Book I. In view of recent realistic revivals I may add that the earlier chapters of Mr. Bradley's _Appearance and Reality_ still seem to me to contain an unanswerable defence of Idealism as against Materialism or any form of Realism, though his Idealism is not of the theistic type defended in the above lecture. The idealistic argument is stated in a way which makes strongly for Theism by Professor Ward in _Naturalism and Agnosticism_--a work which would perhaps be the best sequel to these lectures for any reader {28} who does not want to undertake a whole course of philosophical reading: readers entirely unacquainted with Physical Science might do well to begin with Part II. A more elementary and very clear defence of Theism from the idealistic point of view is to be found in Dr. Illingworth's _Personality Human and Divine_. Representatives of non-idealistic Theism will be mentioned at the end of the next lecture. [1] _Mind_, vol. iv. (U.S.), 1885.