"All of a sudden I hear footsteps in the hall. Someone is looking at me! What does this mean? It means that I am suddenly affected in my being . . . I now exist as myself . . . I see myself because somebody sees me."

-- Jean Paul Sartre in "Being and Nothingness"

It's a classic psychological debate: Which is the real you -- the "inner" private self or the "outer" public person?

"Some people argue that the 'private you' is more important," says psychologist and personnel consultant David Merrill.

"They consider a person's inner motives, thoughts and feelings, the expression of the true self, while the outer behaviors, words and actions are merely illusion.

"But I take the practical view.Since your external actions are the only 'you' most people get to know, to the outside world you are what you say and do.

"Or, as Kurt Vonnegut put it, 'You are what you pretend to be'."

Merrill calls this "outer pattern of behavior" your "social style." And while "everyone exhibits a range of behaviors," each person's typical behavior, he contends, will be one of four styles: driver, analytical, amiable or expressive (for which he gives examples pictured in this page).

"None of these social styles are inherently good or bad. But they do send a message that influences the way that others, in turn, act towards you. Knowing which style you are -- and using that style to your advantage -- can be a major step to business and personal success."

Social style, he stresses, "is not the same as personality, which includes your abilities, attitudes and ideas of what you are and of what you would like to be. But just because it speaks to your outer -- or superficial, if you will -- behavior, doesn't make it less significant."

One example of someone Merrill sees as being out of touch with his own personal style was Richard Nixon as president. "He was a driver, and not very versatile. He sent out lots of mixed signals.

"Reagan is also a driver, but is very expressive and versatile. He extends himself, even with his adversaries, yet you always know where he stands."

Carter, however, was too versatile, says Merrill. "He tried to fit in with every group, and came off too slick for people to trust. He was an analytical driver, but tried to present an amiable style."

Over the past decade, Merrill, 53, has taught thousands of people to use their style through workshops conducted by his Denver-based TRACOM Corp. He has run seminars for corporations such as General Electric and Dr Pepper, and helps businesses use "style awareness" to hire and promote employes and build management teams.

Merrill has trained about 40 instructors around the country to run "style-awareness workshops" which run two to three days and cost about $350. Much of the content is outlined in his new book, Personal Styles and Effective Performance, co-authored with TRACOM vice president Roger H. Reid (Chilton Books, 237 pages, $12.95).

Since social style is defined by how others view you, workshop participants are given confidential questionnaires to distribute to five acquaintances. Their responses to 150 questions are run through a computer to determine a "personal-style profile," which places the participant in one of the four basic styles.

People of both sexes and all races appear equally in all four, says Merrill, whose own style is "analytical, with strong driver qualities." The best groups -- families or offices -- contain people of all styles.

While there is no specific occupational correlation to style -- all actors aren't expressives, for example -- style can affect career direction.

"You might find an analytical doctor in research," says Merrill, "an amiable doctor in general practice, a driver doctor heading a hospital and an expressive doctor doing TV shows and books."

The possibility of changing a style?

"You'll come across as false," says Merrill. "And style itself is not the key to success . . . You don't have to be a driver to make it."

What makes for success in any style "is versatility -- your ability to relate to people of other styles." Many people find it difficult to be versatile "because each of us tends to feel that our own way of acting -- our style -- is the right way to act.

"And it is for us. But how someone else acts is also the right way for them.

"An expressive may sit next to a stranger on an airplane and start up a conversation, while the analytical person would stay aloof. They may argue about which behavior is right -- when, in fact, both are right for them, because each person acts in the way that helps reduce their own tension."

People, says Merrill, "are like thermostats, constantly seeking to reach a state of comfort with others who approach them." Those with low versatility reach this equilibrium by acting defensively -- the way that makes them feel comfortable.

"Likely," he says, "to turn the other person off.

"The key to working effectively with others is developing a sensitivity to and tolerance for the other person's style.

"If we can observe the effect our style has on them, predict the differences and possible conflicts between ourselves and them, we can control our own actions so that we don't create additional tensions."

Since a person's "versatility quotient" is a "pretty good measure of how your audience views your performance," it is calculated on the personal-style profiles given to workshop participants.

Women tend to be more versatile than men, Merrill says, "possibly because most of the women we work with are in business and they may try harder."

Many people have low versatility and get into trouble -- in personal and professional life -- "because they don't realize that the way they see themselves may be vastly different from how others perceive them.

"It's difficult to stand outside ourselves as observers. A little better than 40 percent of the people who try can't guess their own style."

Bosses, contends Merrill, who try to make employes imitate their own style will prove ineffective.

"We're finding that the Japanese are so much more productive, because they work as a team and trust each person to do things efficiently in their own way."

Similarly, parents who try to make children duplicate their style, "may have problems. Think of the father who forces his son to go into the family business, or is very macho and wants his son to be. It's hard, but you've got to learn to love and appreciate your child's own style."

Those who take style-awareness workshops for career development, says Merrill, "report that it helps them in their personal life. That's because it's not a 'me-generation' approach where you get introspective, find yourself and do your own thing.

"It's a 'we-generation' approach where you look at yourself, look at others and discover how you can best work together effectively."