The approval by Congress Wednesday of President Reagan's bill calling for the largest tax cuts in the nation's history drew mixed reaction yesterday from University professors.

Otto Eckstein. Warburg Professor of Economics, said. "This country needed some kind of tax cut, but we definitely didn't need one this big."

Calling the government "generous with money it really doesn't have to give away." Eckstein said "this bill will confront Congress three or four years down the road when the need arises for tax increases."

Robert D. Putnam, professor of Government, said Reagan's bill marks "one of the biggest political gambles of the last two decades," and added that Congress passed the proposal because "both the Republicans and Democrats felt they had the incentive to let Reagan have a try" at improving the economy.

"If the cut produces the boom in the economy that Reagan hopes it will, it could be a major turning point in American politics." Putnam said, adding that "the cuts in social security, student loans and other programs as a result of the bill would all be forgiven by the American people."

But Putnam said that "if the bill doesn't promote a super boom in the economy. Reagan will be in serious political trouble--the Democrats will be in a good position to call the cut a 'rich man's bill,' and the American people will focus on all the services which have been cut."

The bill, whose passage experts have termed the greatest victory in Congress for a president since former President Lyndon B. Johnson pushed his Great Society program through the Senate and the House in 1965, calls for a three-year, 25-per-cent cut in federal income taxes. The bill mandates a five-per-cent reduction this year, followed by cuts of ten per cent a year for the next two years. It is expected to cost the Treasury more than $750 million in revenues.

Congress passed the president's bill over another proposal by several Democrats, calling for a two-year, 15-per-cent cut.

Arthur Maass. Thomson Professor of Government, said "for a political analyst, this kind of thing is very exciting--I would have thought that a lot of special interest groups would have gotten together and stopped this bill."

Maass said "the passage of the bill shows that a strong, charismatic president can turn things around."

While declining to predict a national trend or movement. Maass said the new federal bill and Proposition 2 1 2, the state tax-cutting measure, are "certainly similar," and said, "I think people were just fed up with the Democratic programs."

Benjamin M. Friedman, professor of Economics, said yesterday that the third year of Reagan's proposal "may prove inflationary," adding that "it will come at a time when it might not be obvious that we need a tax cut."

"My guess is that the national deficit will not improve in the foreseeable future, which is unfortunate," he added.

Friedman said he thought the 15-per-cent proposal would have been a "better idea."

"If it came down to a choice between the Reagan cut and no cut at all, I guess I would favor it, but that's not the case," he said