The activity theory, also known as the implicit theory of ageing, normal theory of ageing, and lay theory of ageing, proposes that successful ageing occurs when older adults stay active and maintain social interactions. It takes the view that the ageing process is delayed and the quality of life is enhanced when old people remain socially active. The activity theory rose in opposing response to the disengagement theory. The activity theory and the disengagement theory were the two major theories that outlined successful ageing in the early 1960s. The theory was developed by Robert J. Havighurst in 1961. In 1964, Bernice Neugarten asserted that satisfaction in old age depended on active maintenance of personal relationships and endeavors.