Levett was born near Hull and originally apprenticed to a woollen-draper. He seems to have received some informal education in medicine while he worked as a waiter in a Paris coffee-house1, and he surely worked as a physician afterwards. He seems to have met Dr. Johnson ca. 1746, and he moved in with him ca. 1760 as a live-in companion and doctor. Boswell, in The Life of Johnson, describes him as "an obscure practiser in physic amongst the lower people, his fees being sometimes very small sums, sometimes whatever provisions his patients could afford him." Goldsmith said of him that "he is poor and honest, which is enough to Johnson." 2 Johnson himself described Levett as "an old and faithful friend" and a "very useful and very blameless man".3
Boswell's first mention of Levett is on July 19, 1763, when Boswell inquired about him in a conversation with Goldsmith.