The power and omnipresence of the sexual drive: Next to the love of life it shows itself here as the strongest and most active of all motives, and incessantly lays claim to half the powers and thoughts of the younger portion of mankind. It is the ultimate goal of almost all human effort. It has an unfavourable influence on the most important affairs, interrupts every hour the most serious occupations, and sometimes perplexes for a while the greatest human minds…Sex is really the invisible point of all action and conduct, and peeps up everywhere in spite of all the veils thrown over it. It is the cause of war and the aim and object of peace,…the inexhaustible source of wit, the key to all allusions, and the meaning of all mysterious hints, of all unspoken offers and all stolen glances; it is the meditation of the young and often the old as well, the hourly thought of the unchaste and, even against their will, the constantly recurring imagination of the chaste.
From Irvin D. Yalom’s book The Schopenhauer Cure.