But the Church had known how to deal with intellectual insurgents, from Abelard in the twelfth century down to Giordano Bruno and Vanini in the seventeenth.

They were isolated; they were for the most part submissive; and if they were not, the arm of the Church was very long and her grasp mortal.

And all these meritorious precursors were made weak by one cardinal defect, for which no gifts of intellectual acuteness could compensate.

They had the scientific idea, but they lacked the social idea.

They could have set opinion right about the efficacy of the syllogism, and the virtue of entities and quiddities.