Many of us like to think of ourselves as high achievers, secure in our professional credentials and full of self-confidence.

But life is full of moments when neither the title on the door nor the Bigelow on the floor can protect us from hostility, harassment and outright humiliation.

My emotional Waterloo comes at the car wash. Few combinations of man and machine can more quickly deflate the ego and destroy the mind. Pangs of uneasiness begin as I approach that cavern of cleanliness, edging forward from sunlight into darkness, knowing I must manuever my front wheels onto two narrow tracks and then turn my engine off at the precise moment the machinery catches the car.

Simultaneously, two teen-agers are spraying my front tires and offering a running commentary on my moment of shame:

"Lady, back up and go a little to the left . . . Just turn the wheel . . . Turn the engine off . . . Turn the engine off ! . . . Put it in neutral . . . No brakes!''

By this time I am cowering in my seat, bathed in cold sweat as my car moves through the mechanical bath. I wait for the next humiliating moment, when the kids with the damp rags at other end of the tunnel hoot and holler over my inability to turn the engine on at the right moment and exit gracefully.

Why does my confidence crumble in the car wash?

Like most so-called confident people, I am easy to intimidate once I am outside my own environment.

We are only lions in our own dens.

Take us out of the places we know--where we are known--where we speak the language and understand the rules, and we are as unsure as army recruits on the bus to basic training.

When we need it most, where is the assurance we show in our courtrooms, our kitchens, or our chemistry labs? Why are we speechless when the mechanic tells us that the car repair he promised to complete on Tuesday will be delayed until Thursday? Why do we still let waiters make us feel unworthy of eating in their restaurant if we can't pronounce an entree the way they do in Paris?

Certain experiences turn capable, logical people into quivering masses of protoplasm. One friend says the nurse at the doctor's office makes her feel like she is carrying a social disease if she insists on discussing her symptoms only with the doctor. Another says that the sight of a judge was enough to make him pay his traffic fine without protest--even though he knew he was not guilty.

Of course, we make all kinds of excuses for ourselves--never wanting to admit that we shook when we should have shouted.

The only time we enjoy life's little humiliations is when we watch them happening to someone else--particularly someone whose balloon we were hoping would burst.

I recently watched with glee as a top federal lawyer became a father and learned how fast a baby can bring down the high and mighty. This man, whose word is law in his agency, could not convince his infant daughter to sleep nights. Clearly, the baby did not realize that her father was a presidential appointee.

The last time I saw him, the bleary-eyed solicitor, who previously had spoken to no one below Senior Exective Service level, was soliciting parental advice from typists and trash collectors. No one dared suggest that he read aloud from one of his legal briefs to put the baby to sleep.

It was enough to restore one's faith in justice.