You have learnt something when you can do it right. You are an expert in it when you can't do it wrong.

Bose was born in Philadelphia, Pennsylvania,[3] to a Bengali Hindu father, Noni Gopal Bose and an American mother of French and German ancestry, Charlotte. His father was an Indian freedom revolutionary[4] who, having been imprisoned for his political activities, fled Bengal in the 1920s in order to avoid further persecution by the British colonial police.[5] His mother, Charlotte, is described as an American schoolteacher of French and German ancestry,[6] but Bose described her as "more Bengali than I". She was a vegetarian and deeply interested in Vedanta and Hindu philosophy.