The new "500 days" blueprint for economic revolution in the Soviet Union contains the extraordinary statement: "Mankind has not succeeded in creating anything more efficient than a market economy." Farewell to Marxist illusion.

Here at last is an economic prescription for the Soviet Union that makes no pretense of salvaging socialism. This scheme boldly embraces private property, an independent banking system and stock exchange, elimination of subsidies to industry and the devolution of power to the republics.Soviet President Mikhail Gorbachev has endorsed the 500 days scheme - but always managed to qualify his support. Events are likely to force his hand.

The momentum is clearly with Boris Yeltsin, the madly popular president of the Russian Republic and Gorbachev's arch-rival. Economists working for Yeltsin drew up the plan, to replace an ineffectual one proposed by Gorbachev's prime minister.

There are other obstacles. Gorbachev's top economics adviser, Nikolai Petrakov, who supports moving to a free market, warns that bureaucrats whose ministries and perks will cease to exist with the death of central planning are trying to prevent change. Petrakov describes their opposition as a "scorched-earth policy."

And no one knows whether the Soviet people will take to economic freedom. Taught for 70 years that profit is exploitation, looked after by a low-quality but comprehensive welfare state, they now are asked to trade security for the unproved benefits of capitalism.

The transition will bring layoffs, bankruptcies, price rises and inequality before it delivers a decent standard of living.

The increasingly rapid decline of the Soviet economy leaves little choice but to plunge in, braving the uncertainties and dislocations.

The 500 days plan presents the best hope so far that the Soviet people, who suffered hardship and degradation for decades to no purpose under communism, can now invest their efforts in building a future that works.