Jim Dickson, we have learned, has abandoned his undertaking to sail alone across the Atlantic in his 36-foot boat. There are those who are reassured by his decision for personal reasons (they feared for his safety), and others who are gratified because they saw no point in the undertaking to begin with. I belong in both camps.

But, goodness, what a stir when I wrote to the effect that Dickson's energy, courage and ambition were misdirected. The Post published an irate letter from a deaf student at Cornell University, who construed the point I endeavored to make as an argument against deaf students' going to Cornell (''in fact they're better off,'' was my friend Joe Sobran's comment).

Ted Koppel, who invited Jim Dickson and me to a semi-gentlemanly shoot-out on ''Nightline,'' reproached me for not having made the correct distinction, a point also made by columnist Charles Krauthammer. That distinction, they both say, is as easy as this: although you don't get the full experience if you sail as a blind man, you do get an experience, and who is to say that getting an experience is not worth it to the person getting it? Krauthammer's test is this, and he uses it to describe a deaf man who goes to a ballet: ''Can he {the adventurer} give you an account of what happened? Yes, a partial account. Missing is the rush of the music, but certainly there is an apprehension -- diminished but real -- of the dance.''

A good try, but not worth a whole cigar -- the reason being that when you attend a ballet, you go out to see a combination of music and dance. To see just the dancers and not hear the music is not to have attended a ballet, but to have seen dancers, so to speak, a cappella. Krauthammer declaims: ''Sight is, of course, a large part of the sailing experience. But it is not all of it. If it were, then when Buckley sails into a pea soup fog in which he can no more see water and sky than can Dickson, one would have to say that Buckley is not sailing -- when in fact he is.''

Again, a good try. In my little essay I pointed out that all the senses, specifically including sound and taste, are engaged in sailing but that sight is critical. Never more so than in a pea soup fog, when the eyes strain to see not merely dreadnoughts heading toward you but the sails themselves, the movement of disputatious winds signaling the possibility of a weather change.

Sight is important enough not to be belittled. Another correspondent assaulted me -- by electronic mail, no less -- to advise me that he knows of a 15-year-old girl who disguised her blindness from the judges at a horse show and performed perfectly in a jumping contest. Now, I spent a great gob of my youth in jumping contests on horseback, and I flatly discount any possibility that a blind equestrian can guide a horse around a ring over clusters of jumps and other hurdles without the kind of tactile coordination between hands and horse withers that unify the mount and its rider. This is not quite the same thing as saying that a rider cannot succeed in taking 10 jumps in succession without being dismounted, but to do so would require a static posture, a docile horse and judges who would no more be fooled by what was going on than a listener would be if suddenly the people playing woodwinds started playing the strings and vice versa.

It is a pity that the pity we rightly feel for the handicapped evolves into forced applause when the handicapped attempt that which simply is not natural. Krauthammer says it is not natural to swim the English Channel, yet people do this. He is talking about adventure of an entirely different kind. He is talking about maximum exertion. To have been the first to swim the channel -- after months, perhaps years, of physical and psychological training -- is a feat quite beautiful to contemplate. It is like reading the book or hearing the symphony of a gifted artist totally devoted to his craft.

But to learn that a blind man has sailed across the Atlantic is on the order of being asked to appreciate a book on the grounds that, after all, it was written by a semiliterate. The definitive comment was, of course, Samuel Johnson's, when he said that the wonder of it was not that the dog walking on his hind legs should do so imperfectly but that he should do so at all.

Captain Dickson is a brave man, but his ventures on behalf of the blind are shortsighted.