Several writers have sounded caution over the notion that the diagnostic category of moral insanity was a direct forerunner of psychopathic disorder. As stated by the historian F.A. Whitlock: "there not the remotest resemblance between their examples [Pinel's and Prichard's and what today would be classed as psychopathic personality." Prichard's "moral insanity" was a catch-all term of behavioural disorders whose only feature in common was an absence of delusions: it is not cognate with the modern diagnostic category of antisocial personality disorder. However, Whitlock has suggested that the diagnosis gradually changed into moral imbecility over the turn of the century and that in turn transformed into something like the current concept of psychopathy.