“A thinker does not spend his life in the processes of digestion.” So says Sertillanges. What has this to do with The Intellectual Life? A lot. He quotes the following (I assume these are from Aristotle, but I may be wrong):
The different dispositions of men for the operations of the soul depend on the different dispositions of their bodies.
To a good bodily constitution corresponds the nobility of the soul.
Sertillanges goes on to say that “Minds can only communicate through the body,” and that “the mind of each one of us can only communicate with truth and with itself through the body.” Thus, it follows that (Sertillanges puts this in the form of a rhetorical question) –
… in order to think, and especially in order to think ardently and wisely throughout a lifetime, it is indispensable to subject to the requirements of thought not only the soul and its various faculties, but also the body and the whole complex of its organic functions.
Practical suggestions then follow, such as: “Endeavour to keep well.” “Live as much in the open air.” “Every day you should take exercise.” “Look after your diet.” He also has this to say to lovers of pleasure:
A lover of pleasure is an enemy of his body and therefore quickly becomes an enemy of his soul. Mortification of the senses is necessary for thought…
Very good advice! We’ve heard it all before: A sound mind in a sound body. All that is left is to follow it.