Beginning in the 1940s, Cirlot ascribed himself to the French Surrealist school and to Dadaísm, soon assuming a very broad-horizoned spiritualist tradition of universal longing (Kabbalah, Sufism, and Eastern studies). From this was sparked the interest in symbology that permeated all his literary activity and his important work as an art critic. As a member of the Dau al Set school, he was a collaborator of Joan Brossa and Antoni Tàpies. He conducted comprehensive studies on medieval symbology and hermeneutics, accruing an impressive collection of swords, and his prolific and varied poetic output...more than fifty books...remained independent of the trends that dominated the poetry of the postwar period because of their darkness and hermetism; nevertheless, his impact has never ceased to be reevaluated through continuous revisions, reeditions, appearances of unpublished works, and tributes. The best-known part of his work is the phase of his poetic evolution centered in the actress Rosemary Forsyth, who played Bronwyn in the Franklin Schaffner film
The War Lord (1965) and inspired the permutational phase of his poetry.
As a poet his writing ranges from playful invitations and lexical juggling acts within a general elegiac tone. There are echoes of avant-garde fantasy. As far as his hermetic idea of poetry, Cirlot formulated it in 1968 with these words:
- If I publish few volumes it is because I believe mainly that at the present time, it is very difficult or almost impossible to interest with a new poetic, above all if it revolves around spiritual experiences and not around the problems of the masses. Humanity wants to turn poets into journalists, publicity agents, or priests, very distinct and respectable things in different degrees. But the poet is nothing like that. He alone is somebody that responds to questions formulated by something that resembles nothing. And his voice has resonance that you could not avoid even if you wanted to. That's what hermetism means to him.
Cirlot also cultivated aphorism in his book
Del no mundo (1969), in which his thought can be traced back to its sources in Nietzsche and Lao Tse. In 1986
El mundo del objeto a la luz del surrealismo was published unedited. Written in 1953, it went beyond the conceptual trends of the previous decades and continues to be an essential reference for professors and students of the universe of the work of art. In 1988
88 sueños, a complete collection of the dreams transcribed by Cirlot published partially in the Catalan journal
Dau al Set, was published, clearly showing the importance that the Surrealist school had on his formation.
As a scholar, Cirlot is known internationally from his
Dictionary of Symbols, which continues to be successfully reissued in the wake of symbologists like Carl Gustav Jung, Mircea Eliade, Gaston Bachelard, René Guénon, Gilbert Durand, and Paul Diel. One reviewer in 1962 called the book "a momentous contribution to symbology".