Pope John Paul II
Fides et Ratio §31
Fides et Ratio: On the Relationship Between Faith and Reason
31 Human beings are not made to live alone. They are born into a family and in a family they grow, eventually entering society through their activity. From birth, therefore, they are immersed in traditions which give them not only a language and a cultural formation but also a range of truths in which they believe almost instinctively. Yet personal growth and maturity imply that these same truths can be cast into doubt and evaluated through a process of critical enquiry. It may be that, after this time of transition, these truths are “recovered” as a result of the experience of life or by dint of further reasoning. Nonetheless, there are in the life of a human being many more truths which are simply believed than truths which are acquired by way of personal verification. Who, for instance, could assess critically the countless scientific findings upon which modern life is based? Who could personally examine the flow of information which comes day after day from all parts of the world and which is generally accepted as true? Who in the end could forge anew the paths of experience and thought which have yielded the treasures of human wisdom and religion? This means that the human being—the one who seeks the truth—is also the one who lives by belief.
Source: Fides et Ratio (Vatican.va)