Jerry Brown takes to ideas the way some people take to whiskey. At 43, he is a veteran of seven years of governing one-tenth of America's electorate. He retains his zest for political argument--not idle word-tennis, but serious conversation about what could become a distinctive strand of Democratic politics.

He exaggerates, but only somewhat, when he says "language is everything in this business." If he can find a vocabulary suitable for Reagan's era-- and Reagan's state--his 1982 Senate campaign could test the political appeal of what in Europe is called "social democracy." California is the right laboratory for testing the political appeal of a more "mixed" or "managed" economy.

Brown knows that in California, as elsewhere, there is little support for traditional liberal activism--explicit redistribution of income for egalitarian purposes. But he believes Californians are receptive to a program for more direct government production of "human capital" (trained manpower) and government "targeting" of financial capital.

At one time Brown seemed to favor an almost Franciscan indifference to America's worldly ambitions--ec onomic growth, technological virtuosity. But today he represents the California that believes the slogan on the back of dollar bills--"ovus ordo seclorum." That means, roughly: you ain't seen nuthin' yet.

In recent years high technology, in the form of semiconductors and other electronics, was responsible for one of every four new jobs in California. Brown believes California's, and perhaps the nation's, growth will be driven by information technologies such as computers, software, robotics, biosciences. But California's high-technology industries require 61,000 additional electrical and computer engineers by 1985. California schools will produce fewer than 15,000.

Brown's administration has abolished the capital gains tax for businesses with fewer than 500 employees--the businesses most fertile in technological innovations. Now he favors "joint efforts between industry and government," especially public funding of industrially applicable research, perhaps including the investment of state pension funds to buy equity in "rising" industries. He has created a Commission on Industrial Innovation, including some conservative business leaders, assigned to draft a blueprint for a high-technology future, with public financing of industrial innovations.

Brown's thinking is, in a sense, as American as land-grant colleges, which have been part of the government's spectacularly successful programs for creating science-intensive agriculture. But Brown's evolving vocabulary of "targeting" investment for "emerging industries" and "identified growth sectors" recalls European and, especially, "Japan, Inc." practices. A staff paper says:

"While we do not find it desirable to mirror the Japanese system, of all the American states, California has the most direct interest in developing policies which counter the primary thrusts of Japanese industrial policy because of our high and increasing dependency on technology-based industries."

Brown understands a frequently neglected task of government better than he understands why the task is so frequently neglected. That task is to lengthen society's time horizon, to look down the road to anticipate, or even midwife, new constituencies. But government is constantly driven to preserve the status quo. An institution designed to allocate capital to tomorrow's "winning" industries is apt to be diverted to practicing "lemon socialism," bailing out Chryslers that already have constituencies.

What is needed, Brown says, too blandly, is "basic agreement among leaders" of the regions, government, business, labor, the intelligentsia. If so, what is needed is a miracle. Political allocation of a resource as scarce and valuable as capital is apt to generate conflict rather than consensus.

Brown, however, believes that Californians, who especially appreciate the importance of their university system in their postwar boom, associate public investments with private productivity. They associate their tax payments with private sector vitality. Proposition 13 made California the birthplace of the tax revolt. But Brown says the essence of California remains "an automobile in search of a suburb." That means highways, schools, sewer and water systems, fire protection --in a word, government.

By expressing too many trendy ideas in trendy idioms, Brown armed critics who consider him fluffy-headed. But today he is not trendy; he is leaning against the wind--a gale, really--of disparagement of government. His ideas have serious pedigrees and represent a logical extension of 20th century Democratic policy, which is more than many prominent Democrats can claim.

Brown would not lower the tone of Democratic circles in Washington, where Democrats are proclaiming, insistently, a search for "new ideas." They are conducting such a desultory search that they probably will not find a new idea unless one is served on a silver salver in Mrs. Harriman's drawing room, which is improbable.