This argument has emphasized the professional character of Darwin's early activities, largely in order to balance the usual portrayal of the amateurishness of his early training and field of study. Arguing this way has revealed the interplay between Darwin's personal interests and his professional obligations, the latter being particularly important for the period from October 1836 to July 1837. In several instances, notably the treatment of his collections, the progress of his thought followed the professional lead directly. In the absence (...) of such a lead Darwin did not pursue certain issues, if only for lack of time. Thus the subject of man did not figure in his initial formulation of a transmutationist position. Only after the commitment to the new point of view had been made did the issues emerge which will be treated in Part II of this article. However, we may close by noting Darwin's inherited disposition on the subject: in the summer of 1837 Darwin responded to Lyell's claim that the change from irrational animal to rational man represented “a phenomenon of a distinct kind from the passage from the more simple to the more perfect forms of animal organization and instinct” with a fanciful doodle in the margin.121 The thoughts behind the bemused scribbling were to occupy a good portion of Darwin's time for the next two years. (shrink)