The author argues that to consider the place of facts in psychoanalysis one must first of all distinguish between the use of the term fact in its everyday sense, in which its opposite would be untruth, from the scientific sense in which the term refers to a construction that has been awarded the status of fact by the theory in which it is embedded. Theories in sciences of human behaviour or experience must include not just the hierarchical arrangement of concepts and constructs of the physical sciences, but also the process orientation in which time is the major organising dimension. Facts, as constructs, have different significance in each of these versions of theory, and the meaning of validation, as well as the procedures for determining validity, also differ.