Lepenies was repeating the criticism, first leveled in 1874 by du Bois-Reymond's rival Ernst Haeckel, that the “seemingly humble but actually presumptuous "Ignorabimus" is the "Ignoratis" of the infallible Vatican and of the ‘Black International’ which it heads.” Haeckel overstated his charge: du Bois-Reymond had never supported the Catholic Church, and far from professing humility he reminded his audience that while our knowledge was indeed bounded by mysteries of matter and mind, within these limits “the man of science is lord and master; he can analyze and synthesize, and no one can fathom the extent of his knowledge and power.”