The Road from Here, by Paul Tsongas. New York: Alfred A. Knopf. 280 pp. $12. 95. On June 14, 1980, the Democratic junior senator from Massachusetts, Paul Tsongas, addressed the National Convention of the Americans for Democratic Action (ADA). His talk, widely discussed, jarred an already unsettled Democratic Party by pointing out that the old-style liberalism of the 1960s was inadequate to the problems of the 1980s.
The effort to build a just society at home and abroad through government intervention in FDR's New Deal style had run its course. ''Our case seems less compelling now,'' he told his sobered but attentive audience. ''We must look at the world with fresh eyes, and understand why.''
This book sets out to take that fresh look. It begins with an account of the thinking that led Tsongas into the paradoxical position he now holds: that of a senator with a very high rating from the left-leaning ADA, who nevertheless favors nuclear power and a gasoline tax and who is deeply concerned about such rightist issues as industrial productivity and Soviet expansionism.
The heart of the book is an analysis of what he calls ''eight realities.''
Energy, US-Soviet relations, and the domestic economy are the first three. The fourth concerns the allocation of resources in dealing with them. Next come discussions of the third world, international trade, and the environment, followed by a chapter titled ''Inflation - Effect, Not Cause.''
His cases are well documented, although he is best on energy and the Soviets and weakest (because most preachy) on resource allocation. But through them all he convincingly argues his thesis: that liberal ideals must move from the doctrinaire to the pragmatic. The future of liberalism, Tsongas says, lies in a middle road of ''free market forces softened by compassion.''
It's possibly a self-serving argument for a Democrat to make these days, as the political weather vane swings to the right in a Reaganesque wind. Tsongas's case is especially useful, if you are a junior senator seeking to distinguish yourself from Sen. Edward M. Kennedy, whose family lends its name to the so-called ''Kennedy liberalism'' implicitly under attack here. But one senses below such political practicalities a genuine desire to provide a new basis for the ailing Democratic Party.
This is not, to be sure, a book of philosophy. A senatorial life is too busy for that. ''Much of this book,'' the author admits, ''was composed on airplanes, in airports, during congressional recesses, and at various odd times at home.''
Never mind: at least he wrote it himself, and he is very bright. The book is rather like a lively conversation distilled; and if the result is no tight and scholarly monograph, neither is it the pulpy formlessness of writing by a politician on the hustings. Nor is it simply a memoir, playing to the grandstands with look-what-I've-done bravado. Here, after all, is an elected official willing to think beyond cliche and write with clear (if pessimistic) conviction.