Balancing Newton's mind: his singular behaviour and his madness of 1692-93.

Newton grew up with a vulnerable and eccentric character besides having a low self-esteem, and he was someone who only uncommonly developed any close relationships. On review it is argued that his distrust and suspicions of others, and the fear that he might be harmed by criticism and his discoveries stolen, followed from his mother's separation from him in childhood and not, as has been claimed, from the developmental disorder of Asperger's syndrome. It is further firmly argued that his 'madness' of 1692 and 1693 was due to mercury poisoning from his alchemical experiments and not to clinical depression.