What theory did erik erikson define?

psychological development of human beings and identity achievement

Explanation:

Erik Homberger Erikson (born Erik Salomonsen; 15 June 1902 – 12 May 1994) was a German-American developmental psychologist and psychoanalyst known for his theory on psychological development of human beings. He may be most famous for coining the phrase identity crisis.

James William Middleton (born 15 April 1987) is an English entrepreneur and member of the Middleton family and the younger brother of Catherine, Duchess of Cambridge. In 2013 he founded personalized greeting card company Boomf. In January 2019 Middleton revealed his battle with depression.

Explanation:

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