The probability model is seen by Haavelmo as a convenient abstraction for the purpose
of understanding, or explaining or predicting events in the real world. But it is not claimed
that the model represents reality in all its details. To proceed with quantitative research
in any subject, economics included, some degree of formalization is inevitable, and the
probability model is one such formalization. The attraction of the probability model as
a method of abstraction derives from its generality and flexibility, and the fact that no
viable alternative seems to be available.