"An important distinction exists between prospective and retrospective methods of calculating economic quantities such as incomes, savings, and investments; and... a corresponding distinction of great theoretical importance must be drawn between two alternative methods of defining these quantities. Quantities defined in terms of measurements made at the end of the period in question are referred to as ex post; quantities defined in terms of action planned at the beginning of the period in question are referred to as."

“Correlations are not explanations and besides, they can be as spurious as the high correlation in Finland between foxes killed and divorces.”

“For these anticipations determine the behaviour of the economic subjects and consequently those changes in the whole price system which during a period actually occur as a result of the actions of individuals.”

“There is in fact no contradiction at all between the statement of an exact bookkeeping balance ex post and the obvious inference that in a situation when saving is increasing without a corresponding increase of investment, or perhaps with an adverse movement in investment, there must be a tendency ex ante to a disparity.”

“The further away a scholarly opinion is from direct observation and the more abstract and ‘theoretical’ it is, the more defenseless it becomes against insidious opportunist errors of judgment. In economics, model thinking in particular creates scope for systematic biases... But of course all social studies must nevertheless aim at generalization. It is thus important to be able to think concretely at the same time, as I learnt from Gustav Cassel.”

“Education means an assimilation of white American culture. It decreases the dissimilarity of the Negroes from other Americans.”

“Of all the calamities that have struck the rural Negro people in the South in recent decades—soil erosion, the infiltration of white tenants into plantation areas, the ravages of the boll weevil, the southwestern shift in cotton cultivation—none has had such grave consequences, or threatens to have such lasting effect, as the combination of world agricultural trends and federal agricultural policies initiated during the thirties.”