One evening as Thales was walking along and gazing intently up at the sky, he did not see a big rock in the road just in front of him. He stumbled over the rock and hit the ground hard. As he slowly and painfully got back up, he heard the sound of someone laughing. He looked around and saw an old woman who had also been walking along the road behind him. "O great sage," she shouted, "while you are looking up at the sky, you should also keep an eye on the ground in front of you!"
The moral of the story is that you need to be aware of your surroundings at all times. If Thales lived in the modern world, we might also have to remind him not to text while driving!