Suffering from occasional poor health as a boy, he was educated at home by the Reverend Edward Wilson. An intelligent child, Pitt quickly became proficient in Latin and Greek. He was admitted to Pembroke College, Cambridge, on 26 April 1773, a month before turning fourteen. He studied political philosophy, classics, mathematics, trigonometry, chemistry and history. At Cambridge, Pitt was tutored by George Pretyman, who became a close personal friend. Pitt later appointed Pretyman Bishop of Lincoln, then Winchester, and drew upon his advice throughout his political career. While at Cambridge, he befriended the young William Wilberforce, who became a lifelong friend and political ally in Parliament. Pitt tended to socialise only with fellow students and others already known to him, rarely venturing outside the university grounds. Yet he was described as charming and friendly. According to Wilberforce, Pitt had an exceptional wit along with an endearingly gentle sense of humour: "no man ... ever indulged more freely or happily in that playful facetiousness which gratifies all without wounding any."