It wasn't the Wind Chill Factor yesterday that canceled the presidential inauguration parade; it was the Wimp Chill Factor -- a mind-set that increasingly presumes that the human organism -- particularly the brain -- is not designed to cope with weather.

Does anyone seriously think that, had the parade taken place, those who grew seriously chilled wouldn't have stopped marching and gone inside?

Does anyone seriously think that, had the Redskins been playing yesterday, Robert F. Kennedy Stadium wouldn't have been full?

Why do officials -- particularly in an administration supposedly dedicated to the individual's ruggedness -- underrate the historic ingenuity of people in outwitting the elements? Somebody would have come up with horn heaters for the trombones and electric panty hose for the majorettes. For shared adversity calls forth in people a sense of shared adventure and, ultimately, of shared purpose.

Twenty-four years ago, John F. Kennedy was inaugurated in the aftermath of a paralyzing snowstorm in 22- degree temperatures and a stinging 19-knot wind. To look back on it, the wind chill factor that day was around 10 below zero, but nobody talked about wind chill then. Perhaps it had not been invented.

What they talked about was "vigah" -- a quality of excitement and high purpose that made besting the elements fun. The first chief executive with Addison's disease, who also had the worst presidential back in White House history, summoned people to a national challenge and 50-mile hikes, and a sense of national purpose was born that has been missing ever since.

President Reagan's statement yesterday cited doctors' assertions that the weather "could pose significant risks to the well-being of the many persons who plan to attend and work at" the inauguration.

What happened to the wood-chopping advocate of the strenuous life?

"Under such conditions, exposed flesh can freeze within five to 10 minutes," the statement said.

It can, but it rarely does. If it did, the ski slopes of New England would never open. People are remarkably ingenious in finding ways to keep flesh from being exposed. With a little of the "plain common sense" for which Republicans used to appeal, the flesh of marchers could have been muffled, but not their high spirits.

Doctors would have worried, but doctors always worry, as much about lawsuits these days as about patients. They worried before the Kennedy inauguration, too, but guess what? "Despite the extreme cold, first aid stations along the route . . . did a smaller business than they had expected," says an article from the Jan. 21, 1961, Washington Post.

"A Red Cross spokesman said 152 persons had been treated by the eight aid stations. . . " the article says. "About a third were due to exposure (as hypothermia was then called) and many more to fatigue. Most of these persons were treated on the spot and sent home or to their hotels."

"The total, Dr. J. Lawn Thomason said, was 'under what we expected.' He recalled one inaugural in which the stations handled about 300."

Had events gone on as scheduled, on a volunteers-only basis, many of those scheduled to march might have chosen not to parade. Others might have worked or marched in uniforms augmented with earmuffs, wind masks and electric socks.

But those who took part, particularly the young people, would have returned home proud veterans of an early, visible and highly symbolic testing. They would have borne stories -- and maybe even some scars -- of having done something beyond the ordinary in the name of their community, their state and their country. And in the process, they would have learned something important abou themselves.

By sheltering them from that lesson -- with all the best intentions -- the nation's oldest president sent them a very different message. And that may be the most chilling thing about yesterday's inauguration.