I do conceive that solid proofs must be met by something more than empty and unsupported assertions.

From A Succinct History of the Controversy respecting the Cerebral Structure of Man and the Apes, Evidence as to Man's place in Nature (1863).

I do not mean to suggest that scientific differences should be settled by universal suffrage, but I do conceive that solid proofs must be met by something more than empty and unsupported assertions. Yet during the two years through which this preposterous controversy has dragged its weary length, Professor Owen has not ventured to bring forward a single preparation in support of his often-repeated assertions.

The case stands thus, therefore: Not only are the statements made by me in consonance with the doctrines of the best older authorities, and with those of all recent investigators, but I am quite ready to demonstrate them on the first monkey that comes to hand; while Professor Owen's assertions are not only in diametrical opposition to both old and new authorities, but he has not produced, and, I will add, cannot produce, a single preparation which justifies them.

Plus ça change, plus c’est la même chose

Those pushing civilization forward into new worlds of knowledge faced as many obstructions then as we do today. Professor Owen has many passionate and convinced cognitive off-spring today, still lifting their voices in support of an ideology or belief that is near to their heart but for which they are unable to muster evidence.