Gaius Caligula's mental illness

The strange behavior of the emperor Gaius has been the subject of debate for many historians. Some charge him with madness and attribute it to his illness in a.d. 37, whereas others believe it occurred later, or else had nothing to do with his sickness. We have no real evidence to reconstruct his mental state. Therefore speculations about madness are fruitless, as they can't be proven. Also, his madness belongs to a discourse which originates mainly from the senatorial narrative that sought to discredit him through any means possible. Thus, his acts should be seen from other angles, and the search for 'mad Caligula' abandoned.