MOSCOW, NOV. 26 -- Soviet President Mikhail Gorbachev said in an article today that the goal of his reform program was to provide socialism with a "human face," a phrase that Czechoslovak opposition leaders took as an endorsement of their program and even an implicit apology for the Soviet-led invasion of Czechoslovakia in 1968. Gorbachev's remark came in an astonishing article published here today that also praised the "achievements" of capitalism, including individual liberty and the rule of law. At a huge rally in Prague, Alexander Dubcek, the reformist leader who was toppled after the invasion and now is the symbolic link between the "Prague Spring" of 1968 and the present democracy movement led by the group Civic Forum, repeated Gorbachev's words to the deafening approval of the crowd of more than 500,000. Dubcek, the originator of the slogan "socialism with a human face," has sought a more explicit apology from the Kremlin, one that would finally undermine the legitimacy of the Communist Party leaders in Prague who came to power after the invasion and remain in the leadership. "{On Saturday} Poland and Hungary apologized for the 1968 Warsaw Pact invasion," Dubcek said. "How long will it take before Bulgaria, East Germany and the Soviet Union do the same? The {Czechoslovak} Politburo must also do the same, and it must do so very soon." Gorbachev's lengthy article, entitled "The Socialist Idea and Revolutionary Reform," was printed in today's editions of the Communist Party newspaper Pravda. Leaders of Civic Forum said Gorbachev's language was as close to an apology as they are likely to get from the Kremlin. Several of the Kremlin loyalists who replaced Dubcek in 1968, including party leader Milos Jakes, stepped down two days ago under pressure from the democracy movement. Since Friday, 10 of the 13 members of the Presidium of the Czechoslovak party's Central Committee have been ousted. Gorbachev has shown his approval of the upheavals in East Germany, Hungary, Poland and Bulgaria by using similarly subtle language and references that are sometimes glancing but clearly understood in both East Europe and in the Soviet Union. At a time when every East European country in the Warsaw Pact except Romania is assailing the role of the Communist Party and communist ideology, Gorbachev's article was aimed at showing his determination to "renew" socialism in the Soviet Union well into "the 21st century" and maintain the party's constitutionally guaranteed "leading role." Thoughts of a capitalist system or any other such path, Gorbachev said, are folly. Nevertheless, Gorbachev showed an unprecedented willingness to praise capitalism. Although his article was peppered with approving quotations from the works of Karl Marx and Vladimir Lenin, Gorbachev said the Soviet Union would do well to adopt some of the "achievements" of capitalism, including "equality of all before the law," individual liberty and "principles of the production of goods and equivalent exchange based on the law of value." Marx was wrong, Gorbachev said, to suggest that capitalism's collapse was "inevitable." "In the hullabaloo of our constant confrontation with capitalism, we clearly underestimate the importance of much that has been done by humanity over the centuries," said Gorbachev, adding that prosperity should not be dismissed for ideological reasons. Gorbachev defended the 1917 Bolshevik Revolution as a "world historical breakthrough to the future" but in both his article and his recent meetings he has shown his reluctance to impose that revolution on countries that have rejected its ideology. In another important signal to Eastern Europe, Poland's non-Communist prime minister, Tadeusz Mazowiecki, ended his trip to Moscow with a visit to Katyn Forest in the republic of Byelorussia. The corpses of 15,000 Polish officers were discovered there in 1943. Although the Kremlin insists that the Nazis killed the Polish officers, the Poles, as well as most historians throughout the world, contend that Soviet dictator Joseph Stalin had the officers shot in 1940. Mazowiecki told reporters today that he had raised the Katyn issue with Gorbachev during their meetings here, and he said he expected a full accounting from the Soviets soon. A joint Soviet-Polish commission to investigate the Katyn Forest killings was set up two years ago. Gorbachev, according to the state news agency, expressed his willingness to deal with a Solidarity-led Polish government. The Polish prime minister said he had achieved "mutual understanding" with Gorbachev and also said he agreed with the Soviet Union's objections to a reunified Germany.