The concept of a value-free science is absurd.

It is clear that the building of models is not a purely mechanical process but requires skill of a high order - not merely mathematical skill but a sensitivity to the relative importance of different factors and a critical, almost an artistic, faculty in the selection of behaviour equations which are reasonable, tentative hypotheses in explaining the behaviour of actual economies.

Know this: though love is weak and hate is strong, Yet hate is short, and love is very long.

Accounting for the most part, remains a legalistic and traditional practice, almost immune to self-criticism by scientific methods.

One of the most important skills of the economist, therefore, is that of simplification of the model. Two important methods of simplification have been developed by economists. One is the method of partial equilibrium analysis (or microeconomics), generally associated with the name of Alfred Marshall and the other is the method of aggregation (or macro-economics), associated with the name of John Maynard Keynes.

Economics, we learn in the history of thought, only became a science by escaping from the casuistry and moralizing of medieval thought.

Production functions involving only land, labor and capital... never work and never explain economic development.