ABSTRACT
Biological study, as it is practised today in laboratories and field stations, is essentially a creation of the nineteenth century. The work of Darwin on evo lution, of Mendel on genetics, of Schleiden and others on the cell theory, so transformed the texture of the biologist’s thought that it would be appropriate to attribute to the period 1830-70, rather than to any earlier age, the ‘bio logical revolution’ which completed the modern scientific outlook. The belief in the fixity of species was no less respectable than the belief in the fixity of the Earth; the belief that the Creator must have personally attended to the fabrication of every kind of diatom and bramble was no less primitively anim istic than the belief that His angels governed the revolutions of the planetary orbs. Exactly as the mechanistic philosophy of the seventeenth century was accused of encouraging scepticism and irreligion, on a greater scale (because the issue was more clear and more decisive) the mechanistic biologists of the nineteenth century met the full force of ecclesiastical wrath. The liberty of the scientist to direct his theories in accordance with the scientific evidence alone was equally at stake. But there is this difference. Biology was certainly ‘modern’ - in some respects if not all — before the nineteenth century. A great Renaissance had already occurred, which itself far surpassed all that had gone before. Materials had been heaped up from which a great generalization such as evo lution could be drawn. Above all, the scientific method of biology was already in existence — that was not the creation of the nineteenth century. The researches of Leeuwenhoek and M alpighi, the systematics of Ray and Linnaeus, were preliminaries as essential to the syntheses which introduced the truly modern outlook as the work of Copernicus and Galileo was to that of Newton.
