Well over a century ago, one of the editors of The Atlantic Monthly (probably Bliss Perry) attempted to show how wit and humor, while closely related, can be differentiated. Along the way, he managed to inject more than a little snobbery.

WIT and humor are such elemental, fundamental things,
that it has always been found difficult to analyze them.
Upon some points, however, those who have essayed
this puzzling task agree, for they all hold that wit is an
intellectual, humor an emotional, quality; that wit is a
perception of resemblance, and humor a perception of
contrast, of discrepancy, of incongruity. The incongruity
is that which arises between the ideal and the fact, between
theory and practice, between promise and performance;
and perhaps it might be added that it is always, or almost
always, a moral incongruity. In the case both of wit and
humor there is also a pleasurable surprise, a gentle shock,
which accompanies our perception of the hitherto
unsuspected resemblance or incongruity. A New England
farmer was once describing in the presence of a very
humane person the great age and debility of a horse that
he formerly owned and used. “You ought to have killed
him!” interrupted the humane person indignantly. “Well,”
drawled the farmer, “we did — almost.”

A humorous remark or situation is, moreover, always a
pleasure. We can go back to it and laugh at it again and
again. One does not tire of the Pickwick Papers, or of
Jacobs’s stories, any more than the child tires of the
nursery tale which he knows by heart. Humor is a
feeling, and feelings can always be revived. But wit,
being an intellectual and not an emotional impression,
suffers by repetition. A witticism is really an item of
knowledge. Wit, again, is distinctly a gregarious
quality: whereas humor may abide in the breast of a
hermit. Those who live much by themselves almost
always have a dry humor. Wit is a city, humor a
country, product. Wit is the accomplishment of
persons who are busy with ideas: it is the fruit of
intellectual cultivation, and abounds in coffeehouses,
in salons, and in literary clubs. But humor is the gift
of those who are concerned with persons rather than
ideas, and it flourishes chiefly in the middle and lower
classes.

Wit and humor both require a certain amount of idleness,
time enough for deliberation, — that kind of leisure, in
short, which has been well described as a state of
receiving impressions without effort. Thus we find wit in
the drawing-room, humor in the country-store, and neither
in the Merchants’ Exchange.

Humor is inherent in the nature of things, and even the
dumb animals have some sense of it. When your dog
welcomes you home, wagging his tail and contracting
his lips so as half to disclose his teeth, he is really
smiling with pleasure; and if, as more often happens,
he does the same thing in a moment of embarrassment,
as when he rather suspects that you are about to scold
him, then his smile is essentially a humorous smile.
There is a joke on him, and he knows it.

Rightly considered, the whole universe is a joke on
mankind. “Humor is the perception of those contrasts
and incongruities which are a part of the very texture
of human life.” If, as we believe or hope, man is an
immortal being, is it not a joke that his earthly existence
should chiefly be taken up in maintaining and repairing
that frail shell in which the immortal spirit is contained?
“Humor,” as Hamilton Mabie finely said, “has its source
in this fundamental contrast between the human soul,
with its far-reaching relations and its immortality, and the
conditions of its mortal life. . . . If the mistake which the
boy makes in his Latin grammar involves permanent
ignorance, there is an element of sadness in it; but if it is
to be succeeded ultimately by mastery of the subject, it
is humorous, and we smile at it.” And so of man’s life
viewed as a fragment of eternity. Humor and faith go
hand in hand.

But humor is not only the sudden encounter with some
moral incongruity. There is in addition the sense of
superiority. The victim, for there must always be a victim,
either of his own folly or of some accident, is placed in a
position of inferiority, which constitutes the joke. But is
this all? Why do we laugh? The mere misfortune of the
man is not enough to make us laugh. We do not laugh
when he loses a dollar bill. Nor is the mere unexpectedness
of the incongruity sufficient to make us laugh. We seldom
laugh at wit, which is equally unexpected. The something
further is the sympathetic element. Humor is not simply
the sudden perception of a moral incongruity; it is the
sympathetic perception of it. Thackeray described humor
as a mixture of love and wit. He really meant sympathy
and wit. Humor, it has been said, is laughing with the
other man, wit is laughing at him. The incongruity that
amuses us, that makes us laugh, is the incongruity which
exists between the victim’s state of mind and his conduct
or situation, and that incongruity we cannot appreciate
unless, by the exercise of imagination, we are able to put
ourselves in the place of the victim. Unless we attain this
sympathetic point of view, his conduct may appear to us
right or wrong, logical or illogical, wise or foolish,
fortunate or unfortunate, — anything except funny. If an
ordinary man under ordinary circumstances should step
in a hole and tumble down, the incident would not be a
humorous one. But if the same accident should occur
to a pompous person who was at the very moment
engaged in making a theatrical gesture, the incident would
be humorous; the incongruity between the victim’s state
of mind, sympathetically apprehended by the observer,
and his situation, would be felt as laughable.

One who has the sense of humor well developed can even laugh at himself, taking an external but sympathetic view of his own character, conduct, or circumstances. Without this sense, a man is liable to be deficient in self-knowledge. Who is not familiar with that non-humorous, solemn person who commits the most selfish or cruel acts from what he conceives to be the holiest motives? “A man without a sense of humor,” declares an anonymous writer, “is occasionally to be respected, often to be feared, and nearly always to be avoided.”

— “Wit and Humor,” The Atlantic Monthly,  September 1907, pages 427-428