Only with his studies in ancient Persia did Gobineau come under fire from scholars.[103] He published two books on ancient Persia, Lectures des textes cunéiformes (1858) ("Readings of Cuneiform Texts") and Traité des écritures cunéiformes (1864)("Treatments of Cuneiform Fragments").[103] Irwin wrote: "The first treatise is wrong-headed, yet still on this side of sanity; the second later and much longer work shows many signs of the kind of derangement that is likely to infect those who interest themselves too closely in the study of occultism."[103] One of the principal problems with Gobineau's approach to translating the cuneiform texts of ancient Persia was that he failed to understand linguistic change and that Old Persian was not the same language as modern Persian.[105] His books met with hostile reception from scholars who argued that Gobineau simply did not understand the texts he was purporting to translate.[105]