----------------- HES POSTING ----------------- Lawrence Moss writes: >To summarize, what is exogenous and endogenous is imposed on the >real world by the human mind. I agree. And I would add that it depends on the problem at hand. An excellent example of a theorist aware of this is Keynes. In Ch. 18 of the General Theory, he first re-states his argument by listing the dependent and independent variables and what he takes as given ("this does not mean that we assume these factors to be constant; but merely that, in this place and context, we are not considering or taking into account the effects and consequences of changes in them". p. 245) and by explaining how they are causally linked. He explains (p. 247): "The division of the determinants of the economic system into the two groups of given factors and independent variables is, of course, quite arbitrary from any absolute standpoint. The division must be made entirely on the basis of experience, so as to correspond on the one hand to the factors in which the changes seem to be so slow or so little relevant as to have only a small and comparatively negligible short-term influence on our quesitum; and on the other hand to those factors in which the changes are found in practice to exercise a dominant influence on our quesitum. Our present object is to discover what determines at any time the national income of a given economic system and .. the amount of its employment; which means in a study so complex as economics, in which we cannot hope to make completely accurate generalisations, the factors whose changes *mainly* determine our quesitum. Our final task might be to select those variables which can be deliberately controlled or managed by central authority in the kind of system in which we actually live". Daniele Besomi ------------ FOOTER TO HES POSTING ------------ For information, send the message "info HES" to [log in to unmask]