Answer: The warm praise of the people can cause Caesar to be more powerful and dangerous.
Explanation:
This explains the reason why Brutus killed Julius Caesar. He believed that Caesar was a good man but he did not think it would last as Caesar got more powerful. He believed that Caesar being powerful would corrupt him and make him dangerous.
This is what he meant by the bright day brings out the adder. In order words, the more powerful Caesar is = A brighter day.
Caesar becoming more powerful = the nature of a snake manifesting from him making him more dangerous.
