The etymology of “monster” connects it to words like demonstration and remonstrate. There is an ominous sense here, but also something revelatory. Monsters often serve as mirrors of the society they inhabit — cultural bodies that cast light on the instability of social and scientific categories. The selected “monsters” below come from the 1665 edition of Fortunio Liceti's De Monstris (originally published in 1616 without illustrations), which included more than seventy copies of copperplate engravings by the artist Giovanni Battista Bissoni. Although not the first work on the topic of deformities in nature, De Monstris was perhaps the most influential of the period. In its wake, there was a torrent of interest throughout Europe in so-called “monstrosities”: pygmies, supposed mermaids, deformed fetuses, and other natural marvels were put on display and widely discussed, becoming the circus sideshows of their time.

For Liceti (1577–1657), the monstrous was a matter of form and was classifiable into two major types: uniform and non-uniform. Uniform monsters inhabited multiple categories: deficient, those lacking limbs; excessive, such as polycephalic animals with multiple heads; anything that was both deficient and excessive could be deemed two-natured; if a child was born with fractured bones, it was unformed; and those with an excess of body hair were extraordinary. Non-uniform beings included intersex people, but also man-animal crosses produced from interspecies mingling, and human-demon hybrids. In the images below, congenital disorders mix freely with myth. Headless men (the storied Blemmyes of classical times) rub shoulders with conjoined twins. Scanning across this wondrous panoply of lifeforms, any sense of “normal” begins to feel outdated and maybe even irrelevant.

Breaking with previous treatments of the seemingly monstrous, Liceti did not treat these creatures as “portentous heavenly signs”, argues Touba Ghadessi, but rather “as living beings who expressed certain truths of nature”, whose “deformities elicited the most wonder and admiration” for life’s ability to adapt to adverse conditions. Liceti likened nature to an artist who, faced with some imperfection in the materials to be shaped, ingeniously creates another form still more admirable. “It is said that I see the convergence of both Nature and art”, he wrote, “because one or the other not being able to make what they want, they at least make what they can.”

The author’s preoccupation with matters of birth may have stemmed from his own fraught genesis. His mother went into labor at seven months during a violent sea voyage. When Liceti emerged into the world, he supposedly fit into the palm of her hand, surviving only because his father fashioned a primitive incubator from a repurposed oven. He went on to study medicine and philosophy in Bologna, hold a chair of logic in Pisa, and serve as the first professor of theoretical medicine in Padua until his death. He was known for prodigious writing, releasing a book almost every year of his career, ranging from histories of rings and engraved gems to scholarly treatises on the human soul.