Justice Stephen Breyer’s Supreme Court colleagues on Thursday praised his “optimism and profound love of country,” his “unique questions at argument,” and his “wisdom, integrity and grace,” among other qualities as they reacted to his retirement announcement.

“He is also a reliable antidote to dead airtime at our lunches, moving seamlessly from modern architecture to French cinema, to old radio shows, to a surprisingly comprehensive collection of riddles and knock-knock jokes,” Chief Justice John Roberts Jr. wrote in a statement.