The existence of analogies between central features of various theories implies the existence of a general theory which underlies the particular theo… - Paul Samuelson

In the absence of perfect certainty, the futures prices needed for making the requisite wealth-like comparisons are simply unavailable. So it would be difficult to make operational the theorist’s desired measures. But operational practicality aside, if the theorist specifies in detail the dynamic technology of his model, he will meet none of the pitfalls that come from an attempt to summarize his model by various crude aggregations. The contradictions that result from over-crude aggregation should never be confused with the technical relations that hold at the firm and family level or with the market capitalizations which hold in competitive security and asset markets.

Carry the notion of the individual to its limit and you get a monstrosity, just as you do if you carry the notion of a group to its limit.

As a theorist I have great advantages. All I need is a pencil (now a ball pen) and an empty pad of paper. There are analysts who sit and look vacantly out the window, but after the age of 20 I was not one of them. I ought to envy the new generation who have grown up with the computer, but I don’t. None of them known to me sits idly at the console, improvising and experimenting in the way that a composer does at the piano. That ought to become increasingly possible. But up to now, in my observation, the computer is largely a black box into which researchers feed raw input and out of from which they draw various summarizing measures and simulations. Not having access to look around in the box, the investigator has less intuitive familiarity with the data than used to be the case in the bad old days.