Throughout his life, Stevenson was always interested in mental illness and distortions of the mind and a lot of his novels are based on or involve schizophrenic characters. When growing up he had followed the case of Deacon Brodie - a peaceable cabinet maker by day and murderer by night. In my opinion, he saw the duality as a reflection of his own life; because he too had a split personality. Maybe he was using "…showed first 75 words of 1658 total…

…showed last 75 words of 1658 total…man than an imaginative scientist. Having said this, I believe that he starts out as more an imaginative scientist than an irresponsible man but, as the novella progresses, he becomes more and more irresponsible. Just as Jekyll and Hyde represent the two sides of the same identity, the imaginative scientist and the irresponsible man, in the course of the story; it is the irresponsible man who takes over just as Hyde takes over from Jekyll.