The General Theory of Employment, Interest and Money.

The first edition of Keynes' masterwork, scarce in dust-jacket. Written in the aftermath of the great depression, the General Theory is regarded as one of the most influential social science treatise of the century; it quickly and permanently changed the way the world looked at the economy and the role of government in society. This is the book 'on which [Keynes'] fame as the outstanding economist of his generation must rest' (DNB).

After the 1929 crash, Keynes analysed the classical school of economists, 'and found them seriously inadequate and inaccurate. [...] A national budget, over and above its function of providing a national income, should be used as a major instrument in planning the national economy. The regulation of the trade-cycle [...] must be the responsibility of governments. Lost equilibrium in a national economy could and should be restored by official action and not abandoned to laisser faire. [The General Theory] the economists of the world into two violently opposed camps. Yet eight years later Keynes was to dominate the international conference at Bretton Woods, out of which came the International Monetary Fund (IMF) and the World Bank; and his influence during the ensuing decades, even on his theoretical opponents, has been such that a highly placed American official recently remarked that 'we are all Keynesians today' (PMM).

About speculation especially, Keynes dismisses conventional wisdom, and the fundamentalist's dream, that the fund manager should base his investment decisions solely on the probably long-term yield of any investment 'He who attempts it must surely lead much more laborious days, and run greater risks than he who tries to guess better than the crowd, how the crowd will behave; and given equal intelligence, he may make more disastrous mistakes.' Keynes was speaking from experience. During the Twenties and Thirties, he looked after several institutional funds -- highly leveraged, and highly speculative -- dealing in commodities, currencies, and equities. Like Livermore he was no stranger to loss, and during the 1929 crash his funds lost seventy-five per cent of their value. He managed to recoup, and, amazingly, six years later increased his fortune twenty-three times with a series of judicious investments. As Barton Biggs recently wrote 'there are many brilliant and bizarre characters in today's hedge fund world, but Keynes surpasses them all. Hedgehogs would have liked and appreciated him.'