This is a mechanical age, and the most obtrusive of the current mechanisms is the automobile. It has valves and cylinders and those things that give it power and speed, and rubber tires that it runs on, and a wheel and steering-gear and handles and treadles by which it is directed. Your body, especially your stomach, is the rubber tires; your brains are the cylinders and valves; and your will and the spiritual part of you are the chauffeur and his wheel.
I beg you to be kind to your stomach, as heretofore. It needs no alcohol at your time of life--if ever--and the less you find occasion to feed into it, the more prosperous both your physical and mental conditions are likely to be. I am aware that life, and college life in particular, has its convivial intervals; but you might as well understand (and I have been remiss, or have wasted time, if you do not understand it already) that alcohol is one of the chief man-traps, abounding in mischiefs if you play with it too hard. Be wary, always wary, with it, my son, and especially with hard liquor.
Your mind, like your body, is a thing whereof the powers are developed by effort. That is a principal use, as I see it, of hard work in studies. Unless you train your body you can't be an athlete, and unless you train your mind you can't be much of a scholar. The four miles an oarsman covers at top speed is in itself nothing to the good, but the physical capacity to hold out over the course is thought to be of some worth. So a good part of what you learn by hard study may not be permanently retained, and may not seem to be of much final value, but your mind is a better and more powerful instrument because you have learned it. 'Knowledge is power,' but still more the faculty of acquiring and using knowledge is power. If you have a trained and powerful mind, you are bound to have stored it with something, but its value is more in what it can do, what it can grasp and use, than in what it contains; and if it were possible, as it is not, to come out of college with a trained and disciplined mind and nothing useful in it, you would still be ahead, and still, in a manner, educated. Think of your mind as a muscle to be developed; think of it as a searchlight that is to reveal the truth to you, and don't cheat it or neglect it.