People know that they enjoy traveling with a prefect, but they don’t know the pleasure of a prefect. Do you know what the author takes pleasure in? Please tell me.

In "The Drunken Old Pavilion", "People know that they enjoy traveling with the prefect, but they don't know that the prefect enjoys it" expresses the author:

The author believes that although birds are happy, But it is completely unaware of people's joy; people only know the joy of traveling with the prefect, but they don't know why the prefect is happy. Reading through the full text, we can understand that the author is not only happy for the scenery of Chuzhou, but also for the abundant food and clothing of the people of Chuzhou. I am happy, and I am even more happy that I have managed my illness well. Obviously, the author uses a layer-by-layer, step-by-step approach to express his subjective feelings and pursuit of interests.