“He would live to see people praised for things that were not worthy of praise, simply because truth was seen to be bad for their feelings.” 

Dorrigo will later count himself among the people the public praises, despite doing nothing that is worthy of praise. The truth about people, in his opinion, does not make for a good story. Good stories create personas, and no one can ever truthfully live up to a persona, no matter how much they try. 

“A happy man has no past, while an unhappy man has nothing else.”

Dorrigo is never shown to have any hope for his future, and most of his memories in the novel are bad ones. The closest he comes to happy memories are his times with Amy, but those are not peaceful memories. They are tinged with desperation, obsession, and the knowledge that the war will separate them. He is nothing but his past, and his past is unhappy. 

“No one reads anything anymore. They think Browning is a gun.”

Dorrigo laments to Lynette that the age of technology is producing people incapable of appreciating poetry and literature. This is one more way in which he feels isolated: He has fewer and fewer people to discuss books with. He is not merely out of place among other people but feels displaced from the very era in which he lives.