Inside every classical economist is a modem economist trying to get out. In rereading the Wealth of Nation is, it seems to me that with a little midw… - Paul Samuelson

Error is a virus that tends to spread. As I have already hinted, the categories of circulating capital and of the wage fund tended and still tend to get confounded together.

What is truly discouraging — or reassuring? — is the considerable evidence that the universe of those who seek to be "timers," and vary the fractional shares of their portfolios committed to common stocks in the hope of enlarging average long-term total return, in fact fail to achieve on the average any plus gain in comparison with simply buying and holding a fixed fraction of common stocks.

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.