Sigmund Freud (1856 - 1939) was an influential neurologist and founder of psychoanalysis who believed people are driven by two opposing instinctive desires: the life/libido drive (pleasures including survival and sex) and the death drive/Thanatos (the desire for self-destruction as a means for all living things to return to non-existence). Freud believed that the libido develops in stages during childhood. The first is the oral stage (illustrated by the pleasure of breastfeeding), then the anal (illustrated through the pleasure of toddlers in defecating), then the phallic. In this stage, Freud claimed boys and girls become attracted to the opposite sex parent. They are said to overcome this stage through repression of these socially inappropriate feelings. The subsequent latency stage lasts from around 7 to puberty and is a period where there is no further mental development until the final genital stage, when libido acquires its sexual function and feelings towards the opposite sex cause anxiety because they can be traced back to those for the opposite parent. Freud believed mental health problems originated from the inability to overcome a stage of development through people ‘using up’ too much of their finite libido at one stage and becoming ‘fixated’. Incidentally, Freud committed suicide via a morphine overdose in September 1939. His daughter, Anna Freud (1895 - 1982), built on Freud's work to become a renowned child psychoanalysist who believed that the burgeoning libidinal energy could overwhelm the adolescent, resulting in various kinds of repression and also violence or dishonesty as a reaction to this internal struggle.
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