William James first wrote about the curious warping and foreshortening of psychological time in his Principles of Psychology in 1890: “In youth we may have an absolutely new experience, subjective or objective, every hour of the day. Apprehension is vivid, retentiveness strong, and our recollections of that time, like those of a time spent in rapid and interesting travel, are of something intricate, multitudinous and long-drawn out,” he wrote. “But as each passing year converts some of this experience into automatic routine which we hardly note at all, the days and the weeks smooth themselves out in recollection to contentless units, and the years grow hollow and collapse.” Life seems to speed up as we get older because life gets less memorable as we get older.