Answer:
Hi!
The answer to your question is that he tells Pertelote that dreams are important because the truth is usually revealed through dreams.
Step-by-step explanation:
Chanticleer, while talking to Pertelote, is trying to convey that the answer to his question will come to him. Since Pertelote wants to know who the murderers are, Chanticleer wants him to know that the murderers will be revealed in Pertelotes dreams as these often reveal the truth.