Andrew Russeth at Art News:
Over the course of the more than half-century of relentless experimentation that followed, Ryman radically expanded the possibilities of abstract painting, continuously rethinking how it could be made and what it could look like, even while seeming to confine himself to a single color: white. His death on Friday, in New York, at the age of 88, brings to a close one of the singular careers in postwar America art.
Though Ryman has often been categorized as a Minimalist, that has always felt like an inadequate label for an artist who could build up paint with controlled impasto, as if styling frosting or cement, or with loose, light brushstrokes, or in a deadpan mechanical manner. His work ranges from the resolutely austere to the proudly rococo. It juts out from the wall, is affixed to the wall with tape or screws, and on some rare occasions is effectively a wall itself.
more here.