Like Brutus, whose Stoic proclivities are widely assumed but who is more accurately described as an Antiochean Platonist, Cassius exercised a long and serious interest in philosophy. His early philosophical commitments are hazy, though D.R. Shackleton Bailey thought that a remark by Cicero indicates a youthful adherence to the Academy. Sometime between 48 and 45 BC, however, Cassius famously converted to the school of thought founded by Epicurus. Although Epicurus advocated a withdrawal from politics, at Rome his philosophy was made to accommodate the careers of many prominent men in public life, among them Caesar's father-in-law, Calpurnius Piso Caesoninus. Arnaldo Momigliano called Cassius' conversion a "conspicuous date in the history of Roman Epicureanism," a choice made not to enjoy the pleasures of the Garden, but to provide a philosophical justification for assassinating a tyrant.