"Travelling. This makes men wiser, but less happy. When men of sober age travel, they gather knowledge, which they may apply usefully for their country; but they are subject ever after to recollections mixed with regret; their affections are weakened by being extended over more objects; & they learn new habits which cannot be gratified when they return home. Young men, who travel, are exposed to all these inconveniences in a higher degree, to others still more serious, and do not acquire that wisdom for which a previous foundation is requisite, by repeated and just observations at home.
The glare of pomp and pleasure is analogous to the motion of the blood; it absorbs all their affection and attention, they are torn from it as from the only good in this world, and return to their home as to a place of exile & condemnation. Their eyes are forever turned back to the object they have lost, & its recollection poisons the residue of their lives. Their first & most delicate passions are hackneyed on unworthy objects here, & they carry home the dregs, insufficient to make themselves or anybody else happy. Add to this, that a habit of idleness, an inability to apply themselves to business is acquired, & renders them useless to themselves & their country. These observations are founded in experience.
There is no place where your pursuit of knowledge will be so little obstructed by foreign objects, as in your own country, nor any, wherein the virtues of the heart will be less exposed to be weakened. Be good, be learned, & be industrious, & you will not want the aid of travelling, to render you precious to your country, dear to your friends, happy within yourself. I repeat my advice, to take a great deal of exercise, & on foot. Health is the first requisite after morality.
Write to me often, & be assured of the interest I take in your success, as well as the warmth of those sentiments of attachment with which I am, dear Peter, your affectionate friend."