What should Japan’s homes of the future look like? A few years ago, designer Kenya Hara posed that question to a group of Japanese architects and companies. The result is the House Vision exhibition, open through March 24 in Tokyo. Toyo Ito, Shigeru Ban, and Sou Fujimoto were big names in architecture participating; a carmaker, a bookstore magnate, a forestry company, and other eclectic industries joined in, as well. Here’s what they had to share.