A succinct statement of the author's basic assumptions says: 'Whereas the pressure of the past impels the ego to behave as if it were the id, according to the formula put forward by Nunberg, it is equally true that the pressure of the present may demand of the id that it behaves as if it were the ego—i.e. so that regressive mechanisms may be employed to control reality.' The reconstruction of the past goes along with that of the present. Analysis of the transference both in its progressive and regressive aspect are the prerequisites of genetic reconstruction. The analysis of the past allows anticipation and modification of behaviour in the present; this becomes apparent in the transference neurosis.