"I mean such knowledge cometh to the mind and soul direct, not by way of mere tangible evidence." "And yet, Mr. Hibbs--this is simply mine own ignorance finding a voice--I don't understand why knowledge becomes higher because tangible evidence is lacking, nor indeed why tangible evidence should be despised. But may we return to the matter of definition?" John Kenny glanced at Reuben while the tutor's head was bowed for the inspection of another walnut; Reuben decided it was not merely possible, it was a fact: Uncle John's eyelid _had_ flickered down and up. "What _is_ knowledge?" "Knowledge is the perception of truth." Reuben drank a little, remembering the afternoon. He had spent at least two hours by the pond with Mr. Welland--listening mostly, for once launched the doctor spoke well, like one whose talk had been dammed up a long time: Harvey, Sydenham, a surgeon named Paré, Signor Malpighi again and his little frog, something of a book named _Micrographia_ by a Robert Hooke of England. The time had gone quickly; Mr. Welland was still talking as they crossed the south pasture and climbed the slope, and from the top of it Reuben could see the tiny figures of Ben and Uncle John returning, but the doctor at first was not able to make them out. "My eyes are not what they were," he said, "though maybe I can peer a little way through a stone wall." With that remark Mr. Welland had become somewhat remote, like a man interrupted in conversation by a distant call, though all he did was stand there, his ugly, kindly face turned away from the path of the late lowering sun. John Kenny asked: "And what is truth?" "We must recognize divers degrees of truth," said Gideon Hibbs. "There is the empirical, observational truth I mentioned. There is logical truth, demonstrated by proceeding correctly from the premise. There is ethical truth, not demonstrable by observation or logic, deriving from an ideal harmony between the human will and the will of God." "There I begin to lose you," said John Kenny. "Ideal, sir, attainable in perfection only by the mind, not in common life because man is the plaything of chance, a conclusion to which I am forced, in defiance of prevailing theology, by contemplation of human frailty and the vicissitudes of life." Mr. Hibbs drank and looked a trifle happier. "Above all there is metaphysical truth, even further beyond the reach of observation and logic. Here indeed the philosopher may find consolation--by submission, if you like, to the incomprehensible." "But in what manner is mind not a part of common life?" "Oh? Sir, do you doubt the separateness of soul and body?"