All of Swift's relations with women, and much else in his life, may be accounted for by the supposition that early he discovered or suspected that he was insane, that he believed his insanity might be transmissible, that he was consequently afraid to have children, that he was honest and strong enough to keep himself in check, that the resulting suppression made him irascible and bitter, that he was a vigorous and passionate man, that his quick shifts from tender fooling to savage satire, his friendly and brutal moods, his strutting arrogance that amazed the coffee houses, were not due to any tom-foolery of politics or thwarted ambition in the petty matter of advancement in the church but were due to a conflict, honorably won by Swift, in the place where a man lives. The "early" in this supposition is important. Leslie Stephen, quoting the familiar dark prophecy of Swift at the age of fifty: "I shall be like that tree; I shall die at the top," justly observes that "a man haunted perpetually by such forebodings might well think that marriage was not for him." But Stephen is dealing with Swift in middle age and offering an explanation of why, assuming that Swift was not already married to Stella, he did not marry Vanessa. Let us place the beginning of the perpetual foreboding early in Swift's life and see if the main facts, so far as we know them, will lie upon this supposition.
Swift's attacks of vertigo began in his youth. He attributed his illness to an over-consumption of fruit when he was twenty-one. Swift knew better than that. Even if we assume that medical science in the eighteenth century was stupid and backward, Swift was too intelligent to believe that an early period of indigestion accounted for the suffering which afflicted him all his life. He knew, or suspected and feared, what was the matter with him. In 1699, when he was thirty-two, he wrote some resolutions, headed "when I come to be old." Among them is this: "Not to be fond of children or let them come near me hardly." Stephen quotes a friendly commentator as saying: "We do not fortify ourselves with resolutions against what we dislike but against what we feel in our weakness we have reason to believe we are really inclined to." That friendly commentator was right and understood human nature, though he had never lived (Stephen does not name him) to hear about libido, suppression, defence, inversion, and other wise words now current.