Diagnosing a psychopathic personality type is akin to proving a criminal guilty in court. The criminal defendant will or most likely may, profess their innocence with great zeal. Proving the case against the defendant is similar to diagnosing the psychopath, their actions which makes them a psychopathic type must be proven as they will not readily confess voluntarily on their own. Another way of saying it would be that their "actions speak louder than words" and it is their behavour which marks them as what they are. The words they use are chosen only to confuse and blind you to their true nature.
In summary, judge Paul Ryan not by his speech and double-talk, but rather by his willingness and even outright desire to harm countless others as a stepping stone to achieving his own ends. That is society's greatest tool to use to defend itself against a psychopaths inherently destructive behaviour. Judge him by what he does on the campaign trail, as well as by his voting record. Doing that, the behaviour patterns that he exhibits will quickly reveal his true nature.