Holmes was partially modelled on Doyle's former university teacher Joseph Bell. In 1892, in a letter to Bell, Doyle wrote, "It is most certainly to you that I owe Sherlock Holmes ... round the centre of deduction and inference and observation which I have heard you inculcate I have tried to build up a man",[35] and in his 1924 autobiography, he remarked, "It is no wonder that after the study of such a character [viz., Bell] I used and amplified his methods when in later life I tried to build up a scientific detective who solved cases on his own merits and not through the folly of the criminal."[36] Robert Louis Stevenson was able to recognise the strong similarity between Joseph Bell and Sherlock Holmes: "My compliments on your very ingenious and very interesting adventures of Sherlock Holmes. ... can this be my old friend Joe Bell?"[37] Other authors sometimes suggest additional influences—for instance, Edgar Allan Poe's character C. Auguste Dupin.[38] Dr.