Fourteen years ago, I discovered I was holding a cat by its tail. My cat was a great-grandchild of the breed first identified in 1817 by James Parkinson. In the beginning, my cat was a small kitten-a bad-tempered kitten, to be sure, but still just a kitten.

Those of us with a chronic, progressive illness are scarce enough to be objects of mild curiosity but also common enough that everyone knows, or at least knows of, one or more of us. The present bittersweet stage of modern medical science (it is able to prolong life without necessarily restoring health) ensures that, as time passes, more and more people will become like us. I can speak directly only about Parkinson disease, but I suspect that the human condition is sufficiently general that the experiences of those who have diabetes or muscular dystrophy or rheumatoid arthritis or any other chronic ailment will not be greatly misrepresented by my particular experience.

My cat and I have had 14 years of forced companionship but certainly not 14 years of friendship. My unhappy kitten has grown into a large, angry cat. For 14 years, he has hissed at me, spit at me, clawed me, and bitten me. He has slowed my step and stooped my back. He has slurred my speech and caused me to shake. He has stolen my balance and disturbed my sleep. He gives no quarter. When I get angry and give him a good shaking, he becomes furious and spits and lashes out with his claws. When I try to placate him, he bites me. He demands my full attention. If I turn my face away, he claws my ear. My companion's anger is unrelenting, and the damage he does is both progressive and irreversible.

Essayist and PB [Public Broadcasting Service] commentator Richard Rodriguez has correctly observed that education is not at all concerned with improving students' self-esteem. In fact, children enter school with poor skills, limited imaginations, and heads full of wrong facts. They must learn better skills. They must open themselves to the world as it is. They must put away childish notions. They must cast off self-pride and self-esteem. Then they can learn.

My cat does not care about my self-esteem. He gives me lessons in living with adversity and lessons in how to get around and get along with an increasingly useless body, a body that every day is less and less under my voluntary control. My self-esteem is up to me. If I am offended or embarrassed by my cat's latest attack on my dignity, that's my problem.

Here are some of the lessons my cat has taught me, beginning with the most elementary. My family has my Parkinson disease. That was a hard lesson for me to learn. For a long time I resisted the obvious fact that my condition affected others. I selfishly wanted to keep my disease to myself. Finally, thoroughly annoyed at my willful wrong-headedness, my four children told me in no uncertain terms to grow up and get with it. They wanted a father, not a martyr or a sphinx. They wanted me to take them seriously, to talk to them about my disease and myself, and to listen to them when they wanted to talk.

My bonnie Jean, my wife, has my Parkinson disease; she worst of all. As I slowly succumb to my angry cat, she must work ever harder. Her responsibilities increase as my abilities decline. We who carry the cane get attention. They who walk beside us with tired steps, weary faces, and sad eyes, they who care for us, get none. Yet they bear a heavy burden, and they need support and recognition.

I have finally learned to ask for help when I need it. That was a lesson I resisted learning for a long time. It took me several years before I felt easy about asking for absolutely necessary help in opening a door or in putting on a raincoat. I have also learned to be gracious and accept kind offers of help that I may not really need.

Each time I ask for or accept help, I feel little bits and pieces of my independence slipping away. I feel myself drifting from the kingdom of the healthy to the kingdom of the afflicted, from the society of the competent to the society of those who cannot manage by themselves, from the congregation of the normal to the congregation of the not quite normal.

I have learned that things may not be as they first appear. Some time ago, our daughter Mary mentioned to her mother that Dad should have a wheelchair. Jean told her not to be too quick to mention it to me. She guessed, rightly, that I wouldn't hear of it. Shortly thereafter, a friend told me that she thought I should get a wheelchair for those times when I needed one. I said that I didn't want to be wheelchair-bound.

"How about housebound?" she replied. "Is that what you want?" End of argument. If I stubbornly persist in maintaining habits and attitudes that are no longer useful, I neither learn nor prosper. So, foolish pride, get thee behind me. A wheelchair is not the end of the world.

My cat has taught me that I have within me reserves of strength and patience and courage that I would not have thought possible. I have learned that stubbornness and contrariness are virtues. That makes me very virtuous indeed. Every day, my angry cat forcibly impresses on me the fact that without the love and care of others, I am nothing. I also now know that I should never judge the burdens of others by their behavior. We are all very good at looking better than we are; we all carry burdens in private that we prefer to hide in public.

None of us succeed entirely on our own. Success is as much collective as it is individual. My success in remaining useful over the past 14 years has come at least 50% from my stubbornness. I am not modest about that, but by myself I would be nothing. Three headmasters have stood by me and kept me gainfully employed. For 14 years, my faculty colleagues have held me up and tolerated me. They have not coddled me but have held my feet to the fire and kept me honest and made me do my job, yet they have been patient with me and let me be myself. For that, I am grateful beyond words.

I often refer to my Parkinson disease as my peculiar gift. That distresses my family. But I have always accepted my good fortune and many good gifts without complaint and without acknowledgment or thanks. On what grounds, therefore, should I now complain to the Almighty? Please understand me. I do not like my Parkinson disease. It has robbed me of my independence, taken pleasure from my life, stripped away my self-confidence, sapped my energy, depressed my family, separated me from my friends, driven me from my profession, and darkened my future. Yet it has also, as Mark Twain knew, been able to teach me lessons and give me insights that I could have learned in no other way.

As I look back on my education, three teachers, apart from my parents and my children, stand far above the rest: my first-grade teacher, Miss Davis; my wife, Jean; and my angry cat. Each has given me a wonderful gift.

Miss Davis taught me to read and thereby gave me the world of the printed page. Jean's gift to me has been her personal example of integrity in adversity and her polite but uncompromising insistence that women and girls are entitled to and therefore must be given the same rights and privileges and opportunities as men and boys, a view that is not universally held. My cat's gift to me has been the gift of unwelcome truth. He holds before me the mirror of self-revelation and forces me to stare into it, unblinking.

Until I see myself as I am.