Heard from a friend, some years ago: Three bulls -

Heard from a friend, some years ago:

Three bulls -- a big bull, a medium sized bull, and a small bull -- were
standing by a fence one day, chewing grass and looking out over the
fields. The big one says, "See all of them cows out there? Half of
'em are mine." The medium sized one responds, "See all them cows? A
third of them are MINE." The little bull pipes up, "Hey, all the rest
of them cows are mine."

After a while the bulls notice the farmer drive up with a
truck and unload another bull -- the hugest Brahma bull these other
bulls have ever seen. The big bull stops chewing and says, with a wide-
eyed look, "He...he can have a third of my cows if he wants 'em." The
medium sized bull trembles a bit when he says "He can have HALF of my
cows if he wants them."

Then the two bigger bulls notice that the small bull is
snorting, bucking, pawing the ground, and putting on a ferocious act.
"What are you doing, fool !?" they say. The small bull replies, "I
want to make sure he knows I'm a bull!"