As one of those "atypical oldsters" referred to in William Raspberry's pro mandatory retirement article (op-ed, Dec. 16), I wish to take issue with his arguments and thereby offer what I consider to be a more compelling case for abolishing, rather than retaining, the arbitrary and destructive practice of age-based forced retirement.

His central thesis is that it would be good for older workers and employers alike if, in exchange for job security, a worker would agree to exit his job at some specified age. The argument, while intriguing, is based on four faulty assumptions.

No. 1: Older workers can't compete. Aging workers, according to Raspberry, should not be forced to compete with young workers for their jobs, which is to say they cannot compete. Research over the past two decades refutes this notion. Older workers have been shown to be as productive, less accident-prone, more reliable and, in many cases, better able to make decisions than younger workers. Older executives, too, are in demand now as never before. Business leaders have reportedly become less enamored with executive "whiz kids."

No. 2: Older workers would prefer the predictability of mandatory retirement. Raspberry, of all people, should be aware of the fallacy in this argument. Racism, like ageism, is predictable, but that hardly makes it defensible. An essential commitment to the rights of individuals to be free from bias because of their race, color, creed, national origin or religion not only is fundamentally guaranteed by our Constitution and federal laws, but also has been the driving force behind the civil rights movement. Ageism, of which mandatory retirement is a part, is as odious as racism and sexism. Raspberry's argument that an older worker should be willing to give up his job to a younger worker is analogous to arguing that a black man should be willing to give up his job to a white man at some future date, in exchange for job security now. Such a proposal is paternalistic and nonsensical.

No. 3: Job security should and could be offered by employers in exchange for forced retirement. This assumption gives Raspberry's argument a fairy-tale quality. What employer in his right mind would be willing to offer unqualified job security to anyone for 40 years or more? Workers of all ages should be regularly assessed to determine if they are performing up to par. If they are not, they should be re-trained, re-motivated or replaced. We who fought for the Age Discrimination in Employment Act were not requesting special favors for older workers. We asked only that they be given a fair shake to compete and participate as equals in the job market.

No. 4: Mandatory retirement is necessary because jobs are scarce. The scarcity of jobs has long been used as an excuse to encourage or coerce older workers out of the labor force. This practice is now costing us billions of dollars each year in lost productivity and retirement benefit payments. Older workers are not a drain on society that should be scrap-piled. On the contrary, according to a Data Resources, Inc., report released to Congress recently, an increase in the number of older workers to their level of participation in the work force in 1970 would, by the year 2005, increase the gross national product, reduce inflation slightly and contribute billions in new tax revenues. It would also increase the Social Security trust fund by $10 billion annually.

Perhaps the most destructive aspect of Raspberry's argument is its implication that the young and old are in direct competition for the same jobs. They are not. Seniority rules and the natural progressions that accompany experience mean that older workers generally are in competition only with workers a few years younger than themselves. Fewer than half of 1 percent of younger black workers were affected when Congress raised the mandatory retirement age to 70 from 65 in 1978, according to a Labor Department study. Apparently, the American worker is at least indirectly aware of this. By a margin of two to one, the public rejects the notion that older people should retire to make room for the young.

Rather than developing elaborate justifications for retaining mandatory retirement, we should direct our efforts to the elimination of this last vestige of arbitrary discrimination. Mandatory retirement serves no useful purpose, and it is opposed by nearly all Americans. The productive older worker is not the exception, as Raspberry labeled me and several other older Americans. Rather, there are millions of older machinists, engineers, clerks, sales persons and other Americans who not only are capable of contributing productive talents to society, but are now doing so. With coming labor shortages among youth, the older worker will be in greater demand. We cannot afford to squander this valuable resource.