 Hundertwasser's original and unruly artistic vision expressed itself in pictorial art, environmentalism, philosophy, and design of facades, postage stamps, flags, and clothing (among other areas).The common themes in his work utilised bright colours, organic forms, a reconciliation of humans with nature, and a strong individualism, rejecting straight lines.He remains sui generis, although his architectural work is comparable to Antoni Gaudí (1852–1926) in its use of biomorphic forms and the use of tile.