In the background notes, we read that the author does not believe in symbols. What do you think the tuna means to him?

If this question is about “Ode to Large Tuna in the Market” we can see that for the author, tuna means the finitude of life. This is because the driver is amazed at how tuna was once a strong and vigorous fish, which overcame the adversities of the sea fudge and was full of life, but was surprised by the finitude of life and the feeling that everything comes to end.

With this, the author shows how the struggles and all the vigor we have in life are insignificant, since our life will end anyway.

there is no passage what do you mean?

give me the passage and i will answer your question