Answer: Do not be easily fooled.
Step-by-step explanation:
Time and again the Bear fooled the Coyote yet the Coyote kept trusting the Bear without thinking.
The first time the Coyote was tricked into taking Potato stalks but the Coyote could not be blamed for it was the first time.
The second time however the Coyote should have been more cautious but he wasn't and got fooled again.
The third time, the Coyote still again trusted the bear whom he should have known by then not to be a good friend but instead he let himself get fooled again to the amusement of the bear.
The lesson is therefore to not be fooled easily.