In view of all this we can easily understand the different reception that the book met with from friend and foe. People who had already assented to the main issues of the work on general grounds of probability, were delighted to find these issues decisively established by the plain facts of science. On the other hand, those who would have none of Haeckel’s philosophy now felt compelled, in view of this dreadful work, to call these alleged facts of science themselves into question. In face of this hostility it was some disadvantage that the _History of Creation_ contained a vast amount of technical material (such as the genealogical trees, the Darwinian laws, the explanation of the facts of embryology, &c.) that could only be presented summarily in it, while the proper technical description and justification of them was buried in the thick volumes of the _Morphology_. Haeckel said, over and over again, that a certain thing had been so fully established by him scientifically in the other work that he was now at liberty to take it as a fact; and he accordingly built it up as such without prejudice into the compact structure of the popular work. Readers who wanted to go further into the discussion of these facts had to look up the relevant passages in the larger book. But the great bulk of his opponents—amongst whom we must count even many professional scientists—had never read the two volumes of the _Morphology_. They merely took the brief statement in the _History of Creation_, which was really little more than a reference, and made a violent attack on the “fact” it was said to convey. This led to a great deal of confusion. As in this case a controversy over some petty zoological detail was always a “struggle about God,” and so agitated the opponent down to the most secret folds of his philosophy, the usual consequences did not fail to put in an appearance. Haeckel was branded and calumniated personally. There has never been any apostle in the world that some sect or other has not decried as a rogue and evil-doer, simply because he was an apostle. Wherever Haeckel has made use of any material that did not seem to be absolutely sound in every respect, he was not simply accused of making a mistake, not even of ignorance, but the whole thing has been put down at once to dishonesty and the worst type of bad faith.