In 1836, having completed his education, he entered the Bibliothèque Nationale, and afterwards the Bibliothèque de l"Institut (1844), where he devoted himself to the study of archaeology, ancient and modern languages, medicine and law.
He is mentioned by Freud in The Interpretation of Dreams, and by Sebastian Faulks in Human Traces. He coined the term hypnagogic hallucination and reported a dream that famously inspired Salvador Dalí"s painting Dream Caused by the Flight of a Bee Around a Pomegranate a Second Before Awakening. Alfred Maury was contemporary with Hervey de Saint Denys and the two dream researchers were in disagreement with each other (Blanken & Meijer, 1988).
Gifted with a great capacity for work, a remarkable memory and an unbiased and critical mind, he produced a number of learned pamphlets and books on the varied subjects.
He rendered great service to the Académie des Inscriptions et Belles-Lettres, of which he had been elected a member in 1857. Napoleon III employed him in research work connected with the Histoire de César, and he was rewarded, proportionately to his active, if modest, part in this work, with the positions of librarian of the Tuileries (1860), professor at the Collège de France (1862) and director-general of the Imperial Archives (1868).
lieutenant was not, however, to the imperial favor that he owed these high positions. He used his influence for the advancement of science and higher education, and with Victor Duruy was one of the founders of the École des Hautes Etudes.
He died in Paris four years after his retirement from the last post.