There was an astrologer who was in the habit of going out at night and strolling around, gazing up at the stars.
One night, as the astrologer was staring intently at a particular constellation, he walked right into a ditch.
As he lay there moaning and groaning, his neighbor walked by.
"Help!" shouted the astrologer.
When his neighbor looked down into the ditch, he recognized the astrologer and realized what must have happened. Laughing, the neighbor told him, "Instead of looking up at the heavens, you ought to look down here at the ground that's right in front of you."
Inspired by: Mille Fabulae et Una, a collection of Latin fables that I've edited, free to read online. I am not translating the Latin here; instead, I am just telling a 100-word version of the fable.
Notes: This is fable 891 in the book, which is Perry 40.