IF YOU use a paper cup today, you'll probably feel guilty. Environmental groups at Harvard have done their best to make students aware of the ecological consequences of college life. Plastic plates are being phased out in the houses. Newsprint, aluminum cans and colored paper are being collected and recycled. Campus efforts are part of a national effort to save the environment.

The public effort began last summer, when national environmental action groups commemorated the 20th anniversary of Earth Day. In a frenzy of events designed to push the Earth to the forefront of the national agenda, advocates focused on the little things everyone can do for the environment.

After Earth Day, a torrent of self-help environmental books and pamphlets hit the stands. Replete with tips for ecologically conscious living, these publications tried to make environmentalism accessible to the ordinary public.

This portrayal of environmentalism as simple and easy may feed public awareness of an important national issue; but it can also hurt the ecological cause in the long run. With titles like 1001 Ways You Can Heal the Earth and 50 Simple Things You Can Do to Save the Earth, such publications imply that minimal effort will achieve maximum results.

But environmental issues such as waste disposal and natural resource depletion are neither simple nor easy. Their solutions will be complex and difficult. And painful. Small actions such as avoiding paper cups should be encouraged, but they must be seen for what they are--only the first and the easiest in a series of hard, unavoidable actions that loom before us.

STUDIES show that many consumers have a sense of complacency about the adequacy of small actions. According to surveys conducted by the Center for Energy and Environmental Studies at Princeton, the best energy-saving action most commonly cited by those polled was turning off the lights.

Granted, lights should be turned off. But such efforts should not be regarded as major actions of resource conservation. Turning off the lights is fine. Dumping an armload of newspapers into a box in the hallway in fine. But such virtuous actions are simply not enough.

To really make a difference, Americans should switch from cheap, incandescent light bulbs to more efficient flourescent bulbs. We should weather-strip and insulate our homes. We should trade in our gas-guzzling cars for more fuel-efficient automobiles--and we should try to drive them less. While recycling is better than nothing, we should target the heart of the problem by significantly reducing consumption.

Rather than buying "biodegradable" products (which are ineffective in the sealed, moisture-free landfills currently in use), we should attempt to reduce our three-pound-per day share of the 157.7 million tons of waste generated in this country each year.

Pointing to our dark living rooms is less painful than voting for much-needed energy taxes. It is simpler than supporting tough national energy policy like Singapore's, in which the government limits the number of cars that are licensed and charges a fee for driving downtown. It is easier than setting aside scarce federal funds for research into alternative fuels like natural gas, or limitless power like solar or wind energy.

THIS is not to say, however, that there is no middle ground between activism and apathy. People should alter their lifestyles and their homes. Indeed, such adjustments will be absolutely necessary if environmental solutions are to be forged.

But people should realize that it won't be easy. We need to avoid cultivating the fallacy that what a citizen should do is painless. Such notions only make the already daunting task of saving the Earth that much more difficult.

If we really want to save the earth, we should be ready to sacrifice. We should brace to feel discomfort in our check-books and a decline in our overall standard of living.

To sell environmentalism as simple is to promote a public attitude that makes real changes in a comfortable, wasteful lifestyle more diffcult. And these are changes that are necesary for anything more than minimal progress.

Once upon a time, the earth was dying. Or so the activists said. Now, they tell us that the environment can be saved by 50 easy tips. Does this reversal mean that saving the Earth isn't that big a deal?

We must dispel such potentially disastrous notions. The most challenging task in the fight to save the planet is cultivating a willingness to sacrifice for improvements. This cannot be done if we preach the existence of easy environmentalism.