Venezuela is in dire need of humanitarian aid, and Juan Guaidó, the interim president, has pledged to deliver it tomorrow. Will Nicolás Maduro, the dictatorial leader still formally in power, let him? Ahead of Warren Buffett’s annual letter to shareholders, we look back on a half-century’s-worth of wisdom from the “Sage of Omaha”. And in Japan, longer lives are leading to more books by and for the elderly.