“The value of art is very hard to determine” and it can’t be rationalized, says Ai Weiwei, the Chinese artist and activist, who calls himself “a top businessman.” He discusses when he refuses to sell an artwork, the price of his activism, and why the U.S.-China trade war won’t end up as just a trade war.

Michel Comte is one of the best known fashion photographers of the '90s. He captured Iggy Pop, Claudia Schiffer, Naomi Campbell, and many other superstars. In the past few years, he has been turning away from people photography and towards nature and art.