 Should we regard Descartes’ account of perfect knowledge as a version of the justified true belief analysis of knowledge tracing back to Plato? The above texts are among Descartes’ clearest statements concerning perfect knowledge. Yet they raise questions about the extent to which his account is continuous with other analyses of knowledge. Prima facie, his characterizations imply a justified belief analysis – or using language closer to his own (and where justification is construed in terms of unshakability), an unshakable conviction analysis. There’s no stated requirement that the would-be knower’s conviction is to be true, as opposed to being unshakably certain. Is truth, therefore, not a requirement of perfect knowledge? We’ll return to the issue in  Section 6.4.