Solvitur ambulando: Scientist, Catholic – and Hiker?

In speaking about Pierre Duhem as a man of science and man of faith, it is impossible not to think first of what may be his most memorable statement:

Of course, I believe with all my soul in the truths that God has revealed to us and that He has taught us through His Church, I have never concealed my faith, and that He in whom I hold it will keep me from ever being ashamed of it, I hope from the bottom of my heart.

Such were the words Duhem put almost at the very start of his long and famous essay, "Physics of a Believer." At its end Duhem registered the place, Peyreleau, where he wrote it, and the date, 9 September 1905, when he completed it. A year later, almost to the day, he was back in that quaint village and made a magnificent drawing of it as it is overshadowed by the almost vertical mountainside at the confluence of the Tarn and of the Jonte.

The famous gorges of those two rivers he chose repeatedly for his September hikes, his only form of recreation. Hiking kept him only from his writing desk, not from his constant reflections - scientific and philosophical. Duhem, who composed his writings in his head, found in walking a most effective help for his mind to find answers to many a problem.
[SLJ Scientist and Catholic: Pierre Duhem 11]