The charges against Anaxagoras may have stemmed from his denial of the existence of a solar or lunar deity. According to Laërtius, Pericles spoke in defense of Anaxagoras at his trial, . Even so, Anaxagoras was forced to retire from Athens to Lampsacus in Troad (433). He died there in around the year 428. Citizens of Lampsacus erected an altar to Mind and Truth in his memory, and observed the anniversary of his death for many years. They placed over his grave the following inscription: Here Anaxagoras, who in his quest of truth scaled heaven itself, is laid to rest.