Brooks concluded that the "whole trend of Lacouperie's thought still provokes a collective allergic reaction in Sinology and its neighbor sciences; only now are some of the larger questions he raised, and doubtless mishandled, coming to be hesitantly askable.
He was a descendant of the Cornish family of Terrien, which emigrated in the 17th century during the English Civil War, and acquired the property of La Couperie in Normandy.
Terrien demonstrated that the basis of the work consisted of fragmentary notes, chiefly lexical in character, and noticed that they bore a close resemblance to the syllabaries of Chaldaea.
In 1892, he published the first part of an explanatory treatise The Oldest Book of the Chinese (London, 8 volumes), in which he stated his theory of the nature of the I Ching, and gave translations of passages from it.
He also enjoyed for a time a small pension from the French government, and after that had been withdrawn an unsuccessful attempt was made by his friends to obtain him an equivalent from the English ministry.
[3] Lacouperie's translations and Sino-Babylonian theories that the origins of Chinese civilization lay in Mesopotamia impressed the public but were criticised or dismissed by sinologists then and in following years.
Legge's review of Lacouperie's translation of the I Ching charged that only "hasty ignorance" could have led to the mistakes, which included failing to consult the basic reference, the Kangxi Dictionary.
But the final decline of Lacouperie's comparativist theories of the origins of Chinese civilisation was marked by the attacks of University of Leiden sinologist, Gustav Schlegel.