On the Origin of Species Darwin's ideas with those of Lamarck and Goethe while still reflecting the spirit of "Naturphilosophie". Their ambitious programme to reconstruct the evolutionary history of life was joined by Huxley and supported by discoveries in palaeontology. Haeckel used embryology extensively in his recapitulation theory, which embodied a progressive, almost linear model of evolution. Darwin was cautious about such histories, and had already noted that von Baer's laws of embryology supported his idea of complex branching. Asa Gray promoted and defended "Origin" against those American naturalists with an idealist approach, notably Louis Agassiz who viewed every species as a distinct fixed unit
On the Tendency of Species to form Varieties; and on the Perpetuation of Varieties and Species by Natural Means of Selection of science on which they bear". Years later, Darwin could only recall one review; Professor Haughton of Dublin claimed that "all that was new in them was false, and what was true was old." Despite illness, Darwin pressed on with writing the "abstract" of his "big book" on "Natural Selection"; this condensed version was published in November 1859 as "On the Origin of Species". In a largely overlooked passage from Wallace's essay, he says of the evolutionary principle: The action of this principle is exactly like that of the centrifugal governor of the steam engine, which checks and corrects any