At age 65, Bill Gates continues to walk through life with all of the brashness of an algebra teacher. While his peers among the ultrarich enjoy crocodile breeding, dating pop stars, or traveling by hot-air balloon, the cofounder of Microsoft has devoted his spare time to book collecting and games of bridge. With a soft voice and vigorously boring fashion sense, it’s as if he’s trying to politely underplay his immense success as a businessman or the $36 billion he and his wife, Melinda, have donated to their influential eponymous foundation, which specializes in public health, education, and poverty reduction.