1. Thus Austin Farrer: “The course of modern philosophy is like the story-book Russian journey, where one after another of the sledge-team is thrown to the following wolves: knowledge of body, knowledge of soul, knowledge of knowledge glut in turn the jaws of darkness. But who is the Prince? Which is the sacred person whom we are anxious to convey safe at any sacrifice to journey’s end? He is the ideal of clarity and distinctness, the principle exclusive of all mystery, of everything that is baffling… In the end we have got to make up our minds about the ideal and standard of philosophical knowledge. Either the ideal is subjective — the maintenance of the highest clarity in our own thinking: or it is objective, the fullest apprehension of what really exists, whether we can get our thinking about it perfectly clear or not …” (A. M. Farrer, “The extension of St. Thomas’s doctrine of knowledge by analogy to modern philosophical problems” in The Downside Review, Jan. 1947.)
2. This phrase is half whimsical, half serious. It derives from the charge of Berkeley’s adversary, Jurin, of Trinity College Cambridge, who had sprung to the defence of Newton. According to Jurin, in the Analyst Berkeley had represented Newton, not as the greatest mathematician that ever was, but “the most fortunate, the most lucky mathematician that ever drew a circle … as a good old gentleman fast asleep and snoring in his easy chair, while Dame Fortune is bringing him her apron full of beautiful Theorems and Problems, which he never knows or thinks of: just as the Athenians once painted her dragging towns and cities to her favourite General.” (Philalethes Cantabrigiensis, Geometry no friend to Infidelity: or a Defence of Sir Isaac Newton and the British Mathematicians, London 1734, p. 65). While the notion of a state between sleep and discursive reasoning came to Berkeley in this fortuitous way, it is not, in fact, an inappropriate description of that condition of rest and contemplation, after much intellectual labour, from which emerges a sudden intuition of the truth with regard to the matter in hand.
3. How Berkeley would have rejoiced at the astonishing achievements of the Indian mathematician Ramanujan! This gifted man evolved abstruse mathematical theorems, many of indubitable veracity, from what appeared to be the slenderest foundations. See G. H. Hardy et al, Collected Papers of Srinivasa Ramanujan (Cambridge 1927). The subtly analogical and inductive, rather than strictly demonstrative, character of original mathematics is plain for all to see in Ramanujan, and is only slightly concealed in Newton. The older Berkeley would hold that this inspirational character is found at the centre of all creative mathematics and science. That scientific achievement of the first order requires intense prior application, but when it comes it has roots which are ultimately mysterious, is a commonplace today. In Berkeley’s “age of enlightenment” it must have been a startling claim: not least to Berkeley himself, who entertained no such notions in his youth.
4. The spirit of serious play pervades all the Platonic dialogues; in the Laws it receives explicit formulation (e.g. 688b, 803c). A careful statement of his meaning is to be found in Ep. vi, 323 d: Plato urges the three recipients of the letter to work together in friendship, and to swear a covenant to this effect, “with an earnestness that is not graceless (amousos) combined with a playfulness that is sister to earnestness.” A cognate notion appears in Aristotle’s eutrapelos, the man who preserves the mean between the buffoon and the boor (Eth. Nic. IV, viii; X, vi). After Aristotle, the notion is taken up in various forms in patristic theology. From the Eth. Nic. it reaches Aquinas (Summa Theologica II, II, 168, 2) and so is infused into medieval theology. (See Hugo Rahner Man at Play, English translation London 1965). J. Huizinga in his Homo Ludens (English translation London 1949) provides a veryinformative survey of the leavening element of play in human affairs. In Ch. ix he traces the emergence of philosophy from the riddle games of archaic society: an evolution either to that upward soaring play in which Plato found truth; or downwards to the graceless nether-world of the intellectual quack.
5. The Dialectic of Immaterialism p. 26.