Quote from the encyclical letter, fides et ratio, of the supreme pontiff John Paul II to the bishops of the Catholic Church on the Relationship Between Faith and Reason given in Rome, at Saint Peter’s, on 14 September 1998.
“Although times change and knowledge increases, it is possible to discern a core of philosophical insight within the history of thought as a whole. Consider, for example, the principles of non-contradiction, finality and causality, as well as the concept of the person as a free and intelligent subject, with the capacity to know God, truth and goodness. Consider as well certain fundamental moral norms which are shared by all. These are among the indications that, beyond different schools of thought, there exists a body of knowledge which may be judged a kind of spiritual heritage of humanity. It is as if we had come upon an implicit philosophy, as a result of which all feel that they possess these principles, albeit in a general and unreflective way. Precisely because it is shared in some measure by all, this knowledge should serve as a kind of reference-point for the different philosophical schools. Once reason successfully intuits and formulates the first universal principles of being and correctly draws from them conclusions which are coherent both logically and ethically, then it may be called right reason or, as the ancients called it, orthós logos, recta ratio.”