Influences from other reference-groups reach out in quite comparable fashion; and teachers in their work are thus both strengthened and enfeebled by the secret pressure of the whole community which has wittingly or unawares moulded the self-pictures of the pupils along with those other hypotheses, expectancies or sets which they bring with them to each act of perception. There is in adolescents as in all human beings an upthrust of growth and a trend to self-improvement; but where this is met with courtesy and understanding its direction is not necessarily antagonistic to the purposes and longings of parents and older friends. It has sometimes been suggested that life in school is very different from life 'in the world outside'. The resources of the community contribute to the strengthening or the enfeebling of teachers. The social services of a modern state include the provision of probation officers, mental deficiency officers, nursery schools, special schools, child guidance centres, and the like.