…even during Feuerbach’s lifetime, natural science was still in that process of violent fermentation which only during the last 15 years had reached a clarifying, relative conclusion. New scientific data were acquired to a hitherto unheard-of extent, but the establishing of interrelations, and thereby the bringing of order into this chaos of discoveries following closely upon each other’s heels, has only quite recently become possible. It is true that Feuerbach had lived to see all three of the decisive discoveries — that of the cell, the transformation of energy, and the theory of evolution named after Darwin. But how could the lonely philosopher, living in rural solitude, be able sufficiently to follow scientific developments in order to appreciate at their full value discoveries which natural scientists themselves at that time either still contested or did not know how to make adequate use of? The blame for this falls solely upon the wretched conditions in Germany, in consequence of which cobweb-spinning eclectic flea-crackers had taken possession of the chairs of philosophy, while Feuerbach, who towered above them all, had to rusticate and grow sour in a little village. It is therefore not Feuerbach’s fault that this historical conception of nature, which had now become possible and which removed all the one-sidedness of French materialism, remained inaccessible to him.
Frederick Engels, Ludwig Feuerbach and the End of Classical German Philosophy, 1886
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