William Crathorn

William Crathorn (fl. c. 1330) was an English Dominican philosopher from Oxford, known for his work in epistemology, philosophy of language, and ontology. He was influenced by William of Ockham and sought to advance philosophical thought. In epistemology, Crathorn explored the nature of knowledge, positing that we perceive mental likenesses (species) of external objects, drawing parallels to Kantian ideas. He argued that concepts are mental qualities and that our minds mirror concepts, limiting our understanding to natural concepts of qualities. To counter skepticism, he used the cogito-argument to affirm certainty of mental activity. In the philosophy of language, Crathorn investigated the linguistic aspects of science, suggesting that the "total significance" of a proposition is key. He revolutionized thought by proposing that words precede ideas and shape them, challenging the notion of a universal mental language. Crathorn also revised Aristotelian categories, believing the human mind primarily knows qualities and cannot be certain of their existence without divine assurance. His work includes 'Quaestiones super librum sententiarum'.