Maybe Biden is thinking of the Julio who is mentioned in one of the Simon and Garfunkel songs. Of course the Simon and Garfunkel music is from a later generation than Biden’s.
Biden was born in 1942.
Simon and Garfunkel were both born in 1941.
Biden was already a Senator when the song came out, but he wasn't from an earlier generation.
Biden doesn’t think.
He just has mental outbursts/bursts passing instead of thoughts.