I’ve just finished reading Arthur Brooks’ book From Strength to Strength, and it deeply resonated with me (thank you Gregory Rubin for the tip). The central message is clear: life has two halves, and fulfillment comes when we recognize the transition from one to the other. In the first half, many of us thrive on fluid intelligence — ambition, innovation, achievement. But over time, what brings the greatest meaning is not “more of the same,” but a shift toward crystallized int