He became an enthusiastic biologist; and a warm admirer and disciple of Goodsir, in whose philosophical tendencies he found, like many of his friends, the inspiring direction that soon became so marked and characteristic a feature of his scientific work and aims.

In his inaugural address, delivered in 1859, as a President of the Royal Medical Society, he supposes the questions, Dickson graduated as doctor of medicine in August 1860 with his thesis on 'On the development of the flower, and especially the pistil in the caryophyllaceae',[4] having previously, in accordance with his biological proclivities, studied under Albert von Kölliker in Würzburg and Rudolf Virchow in Berlin.

In the latter year, the professorship of botany in the University of Edinburgh became vacant, on the resignation, caused by failing health, of the renowned and veteran Professor John Hutton Balfour; and to this great botanical position, Dr Dickson was promoted by the Curators.

We find him entering on his duties imbued with the same conception of the far-reaching affinities between science and art or practice as was recognised in the early developments of his biological career.

The same lesson was indicated as, 20 years before, he had taught in his inaugural address to the Royal Medical Society, that the cultivation of every department of biological science increases the knowledge'of that human anatomy which is the foundation of the art of medicine and surgery.

A glance over the appended list shows his great partiality for subjects bearing on development and morphology, in which departments of botany he acquired the position of an eminent authority.

He strenuously opposed the legislative attempts, which fortunately proved abortive, to modify the special characters of medical education and graduation in the Scottish universities, for the mere sake of bringing them into harmony with the systems prevailing in the southern division of the United Kingdom.

He looked with much distrust on the schemes, embodied in the various Bills introduced into Parliament during the last seven years, for effecting fundamental changes in the constitution and character of the Scottish universities; considering them prompted more by political, social, and selfish aims, than by a real and disinterested desire for educational reform.

When not engaged in teaching or in the botanical investigations to which he was so ardently attached, his occupations as proprietor of Hartree and Kilbucho, and social intercourse with his friends, were more in accordance with his tastes.

And the same characteristics made him also a general favourite in society; where he used to delight his friends by the exquisite taste and feeling with which he played on the piano the works of Beethoven and Bach, and the national airs of Scotland.