Rachel Whiteread

Monument, 2001 Whiteread answered the empty plinth with the plinth itself: a cast of it in transparent resin, set upside down on top of the original. A sculptor known for casting the empty spaces in and around everyday objects and buildings turned the problem of what to put up there into the artwork. Being clear, it changed with the London light and weather rather than standing against it. As a closing statement for the RSA's experiment it was hard to beat, because it made everyone look at the empty plinth one last time.