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
Reactions to On the Origin of Species and "lifting an immense Bible first with both and afterwards with one hand over his head, solemnly implored the audience to believe God rather than man". As he admitted that the "Origin of Species" had given him "acutest pain" the crowd shouted him down. Hooker's "blood boiled, I felt myself a dastard; now I saw my advantage–I swore to myself I would smite that Amalekite Sam hip and thigh", (he was invited up to the platform and) "there and then I smacked him amid rounds of applause... proceeded to demonstrate... that he could never have read your book... wound up