Harry Harlow's classic article "The Nature of Love" was published in the journal American Psychologist. Originally presented the year before as his presidential address at the sixty-sixth Annual Convention of the American Psychological Association, this famous text is where Harlow challenged the prevailing behaviorist notion that emotive subjects such as love and affection were not suitable topics of psychological inquiry.

In doing so, Harlow drew heavily upon his controversial experimental work on love and isolation effects among infant rhesus monkeys who had been separated from their mothers 6 to 12 hours after birth and whose affectional responses to cloth and wire 'surrogate mothers' demonstrated the importance of "contact comfort."