Anyone who thinks sensibly about most things has a right to be utterly dotty about some things. Howard Baker, in his campaign to get television cameras into the Senate chamber, is exercising his right with a vigor that deserves a larger, better cause. Cameras in the chamber would not be good for the republic, the Senate or journalism.

Proponents accuse opponents of opposing an "open" (Baker's word) Senate and favoring "secret deliberations" (Baker again). But the Senate already is a fishbowl in a spotlight. Cameras are allowed into most committee meetings, where most Senate business is performed--and where, perhaps not coincidentally, most of the demagoguery occurs.

In the Capitol, senators have provided themselves a studio where they can make their own programs, and have provided broadcast journalists with facilities for conducting interviews. There are press galleries in the chamber. And Jack Danforth (R-Mo.), Missouri's finest ornament since Stan Musial, notes that the Congressional Record prints every word uttered in the Senate, and many that are not actually uttered.

Baker notes that the Senate, which during its first seven years met behind closed doors, voted in 1794 to provide public galleries. Baker says that "introducing broadcasting to the chamber merely extends the gallery." The charitable response to that thought is: oh, my.

Differences of degree often involve differences of kind. Debating in front of a few hundred, say, high school students on their senior trip from Missoula is different from performing in front of cameras that may, if one says something sufficiently pithy, or reckless, carry what one says to 20 million voters. And people in the gallery, unlike viewers of evening newscasts, hear more than 30-second snippets of debate, snippets wrenched from context and sandwiched between commercials for denture adhesives.

A camera is a constricting news-gathering instrument, and network newscasts are restricted to about 22 minutes of news. Hence the tendency to fill the time with footage of episodes that are vivid and brief. Cameras in the Senate would strengthen that baleful tendency by adding a new source of such footage.

Senators can provide such vivid, brief episodes, but should they be encouraged to? The Senate is supposed to be a place for calm and extended discussion.

Some argue that because the House of Representatives is televised, the Senate should be, too. But that non sequitur springs from careless consideration of the Constitution. The Constitution clearly intends for the Senate a more detached, aloof and deliberative role than that of the House, which is a more purely representative institution.

Danforth notes tat the Senate already is "overloaded," that there is little "slack" or "empty space" in senators' lives, which are constantly chopped into maddeningly smaller segments. Senators despair of finding larger blocks of calm time in which to deal with large issues, so they become habituated to achieving satisfaction, or at least recognition, from "dealing with some little thing which is colorful."

Danforth believes that things might be made worse by television's incitement to the "60-second quick trick." Most--about 99.5 percent--of a good senator's work is done not in the chamber but in committees or his office. Danforth says the telling question is: if the chamber is televised, will senators apportion their time as they do now? Surely many will be drawn from other duties, to the chamber.

The networks (and here I bite a hand that feeds me) are at least as nimble as journalists generally are at cloaking their self-interest in the rhetoric of altruism. When journalists start exclaiming about "the public's right to know"-- to know about Al Haig's confidential remarks, or whatever--they sometimes are correct about the public's right. But they invariably are demanding something that will serve their professional-commercial interest in spicier journalism.

It is naive or arrogant or cynical for journalists blandly to assert that whatever serves their interest in ever-wider and more direct access to government serves, necessarily and automatically, the public interest. The public's primary interest is in good government, and there is tension, not perfect harmony, between that goal and journalists' more parochial goals. The tension is apparent in the argument over televising the Senate.

There is such a sufficiency of reasons for opposing the televising of the Senate, we opponents can generously discount one argument against televising: the fear that cameras in the chamber will excite senators' presidential ambitions. Must sharks' appetites be stimulated by aperitifs?