The year 2023 marks the 700th anniversary of the canonization of one of the most influential saints of the Catholic Church, Thomas Aquinas. Born in southern Italy in 1225, Aquinas is one of the 37 Doctors of the Catholic Church, a title that emphasizes an individual's impact on the doctrine and teaching of the Church. Widely considered one of the greatest thinkers in the Western Canon, the work of Aquinas has influenced generations in their pursuit of truth, regardless of faith or creed. Despite living only to the age of 48, he still managed to amass over 10,000,000 words in some 60 works of philosophy and theology.1 His prolific writing and nearly illegible handwriting caused a 13-century source to aver that he “used to dictate in his cell to 3 secretaries, and even occasionally to 4, on different subjects at the same time,”1 with nearly illegible handwriting (Figure 1).2 The brilliance needed to maintain this intense level of production and scholastic clarity remains unmatched.

Aquinas' most famous work is the Summa Theologica, arguably one of the greatest works of philosophy and theology ever written. He also wrote many commentaries on the works of Aristotle, synthesizing the ancient classical thought of this pagan philosopher with the medieval scholastic methods of theology, philosophy, and discourse (Figure 2, portraits of Aquinas).3,4

At the time, the emphasis on the thought of pagan philosophers such as Aristotle was highly controversial within the Catholic Church. Aquinas greatly championed the synthesis of faith and reason, a concept that continues to influence modern epistemology, including within the context of the modern scientific method.

No commemoration of Aquinas' life can exclude consideration of its end. Controversy surrounds the true nature of his death, with theories ranging from a nondescript sudden illness to an assassination with poison by the king of Naples.5 Recent scholarship has pointed out the potential neurological nature of his death from a stroke or an epidural hematoma.6 On his journey to Lyon, France in 1274, one biographical account describes an otherwise-healthy Aquinas sustaining a traumatic injury to the head that seemed to mark the beginning of his demise. From the symptoms, timeline, and nature of his injury, we postulate that Aquinas died of a growing chronic subdural hematoma secondary to a head injury sustained several weeks before his death.