Philosophy is Concerned With Truth Not the Opinions of Philosophers

"[S]tudium philosophiae non est ad hoc quod sciatur quid homines senserint, sed qualiter se habeat veritas rerum."

"The study of philosophy does not mean to learn what others have thought but to learn what is the truth of things."

St. Thomas Aquinas, De Caelo et mundo, I, 22, 228
Quoted in Josef Pieper, The Silence of St. Thomas, London: Faber, 1957, 42.

"Latin Averroism is fundamentally the forerunner of the Renaissance and, therefore, of modern philosophy and science in general...the purely historical approach to the interpretation of philosophy--the opinion that the true object of philosophy is its own history. For Siger of Brabant, the leader of the Averroists at the University of Paris, the study of philosophy signifies the exploration of the historical systems of philosophy, irrespective of whether they were true or false. Here for the first time appears that modern type of philosopher who, instead of discussing his true subject, reality, discusses something quite different, the philosophies." Ibid. 41-42.