I have quoted on various occasions A. J. Liebling's observation that freedom of the press belongs to whoever owns one. He was not, I suspect, talking about absolute freedom, because capitalism and the market economy place certain limits on us. Our mass "media," for example, theoretically are free to refuse all advertising. But no one has found a formula for surviving without it. Audiences inhibit our freedoms. The television networks are free to dump their Dan Rathers, the soaps, movies, game shows and professional football and to broadcast instead congressional proceedings and city council meetings 24 hours a day. That "freedom" is hypothetical; the deafening prospect of millions of OFF buttons being pressed simultaneously and permanently is too horrid to contemplate.

The Post and other newspapers are free to purge themselves of sports news, business and financial news, comics, crossword puzzles, weather reports, TV listings, movie and restaurant reviews, recipes and all other nonpolitical and nongovernmental material. That, most likely, would solve in a hurry our newsprint recycling problem and create a critical shortage of fish wrappers.

These market inhibitions have not been present in our time in Eastern Europe, the Soviet Union, China and much of the rest of the world. In those societies with "command economies" press "freedom," like the meat markets and all else, has belonged to the state and party bureaucracies. Their "media" have been ad-free and trivia-free and straitjacketed by all the constraints totalitarianism implies.

Change is at hand. From Moscow to East Berlin, capitalists and their handmaidens from the advertising world are at the gates, hopeful that within five to 10 years consumer societies will have flowered and that a "free press" by Western standards will have prospered too.

Pravda, the dogmatic ideological organ of the Communist Party Central Committee in the Soviet Union, is an unlikely symbol of what this brave new world may bring. Its New York correspondent, Victor Linnik, a suave operator who occupies a luxury apartment on the East Side, has started working Madison Avenue as an ad salesman. Pravda's price: $50,000 a page for an audience of 8 million. Moscow News, a lively and politically unorthodox weekly, is taking ads and spreading its commercial net to London, Paris and other cities around the world.

Russian editions of PC World, Omni and Scientific American are gaining footholds in the Soviet market. A new Russian edition of Business Week is imminent; Reader's Digest, Prevention and The New Farmer will not be far behind. The International Herald-Tribune, in which The Post is a partner, is selling 1,500 copies a day in Moscow and other cities and is considering a joint venture for the printing of a Russian edition on Soviet presses. Playboy is publishing a Hungarian edition with an eye on advertising revenues that already have reached $140 million in that country. Business Week has a Hungarian edition. The Australian/American media tycoon Rupert Murdock has bought a 50 percent interest in two new and hot Hungarian magazines that already produce several millions in profits from advertising and circulation.

Other American publishers in collaboration with the U.S. Information Agency, hope to whet the appetite of Soviet and East European consumers this month with samples of Time, Life, Popular Science, Vanity Fair, High Fidelity, Elle and other consumer magazines. From 10 to 40 copies of approximately 60 magazines will be distributed to libraries and other institutions throughout Poland and Hungary. If shipping problems can be overcome, millions of unsold U.S. magazines would be available under this program for distribution throughout Eastern Europe. The object: a generation addicted to Western-style journalism.

As the market economy develops in these countries, private owners will compete directly with government and party organs for "media" dominance and for the intellectual loyalties of hundreds of millions of people. The Marxist doctrine that "advertising is an unfair capitalistic method of competition" cannot withstand those $50,000 page-rates in Pravda. It will be interesting to see if Pravda itself can withstand the cultural competition from a Slavic journalism encompassing versions of "Blondie," Ann Landers and the horoscope. Don't bet the collective farm on it.