What a character was Sir Isaac Newton! He is described as modest, candid, and affable, and without any of the eccentricities of genius, suiting himself to every company, and speaking of himself and others in such a manner that he was never even suspected of vanity. "But this," says Dr. Pemberton, "I immediately discovered in him, which at once both surprised and charmed me. Neither his extreme great age, nor his universal reputation, had rendered him stiff in opinion, or in any degree elated." His modesty arose from the depth and extent of his knowledge, which showed him what a small portion of nature he had been able to examine, and how much remained to be explored in the same field in which he had himself labored. In a letter to Leibnitz, 1675, he observes, "I was so persecuted with discussions arising out of my theory of light, that I blamed my own imprudence for parting with so substantial a blessing as my quiet, to run after a shadow." Nearly a year after his complaint to Leibnitz, he uses the following remarkable expression in a communication to Oldenburg: "I see I have made myself a slave to philosophy; but if I get free of Mr. Linus's business, I will resolutely bid adieu to it eternally, excepting what I do for my private satisfaction, or leave to come out after me; for I see a man must either resolve to put out nothing new, or to become a slave to defend it." His assistant and amanuensis for five years (Humphrey Newton) never heard him laugh but once in all that time: "'Twas upon occasion of asking a friend, to whom he had lent Euclid to read, what progress he had made in that author, and how he liked him. He answered by desiring to know what use and benefit in life that study would be to him. Upon which Sir Isaac was very merry." He was once disordered with pains, at the stomach, which confined him for some days to his bed, but which he bore with a great deal of patience and magnanimity, seemingly indifferent either to live or to die. "He seeing me," said his assistant, "much concerned at his illness, bid me not trouble myself; 'For if I die,' said Sir Isaac, 'I shall leave you an estate,' which he then for the first time mentioned." Says Bishop Atterbury, "In the whole air of his face and make there was nothing of that penetrating sagacity which appears in his compositions. He had something rather languid in his look and manner, which did not raise any great expectations in those who did not know him." When Pope expressed a wish for "some memoirs and character of Newton, as a private man," he did "not doubt that his life and manners would make as great a discovery of virtue and goodness and rectitude of heart, as his works have done of penetration and the utmost stretch of human knowledge." When Vigani told him "a loose story about a nun," he gave up his acquaintance; and when Dr. Halley ventured to say anything disrespectful to religion, he invariably checked him with the remark, "I