Sierhuis, Johannes AlphonsusB: 12.21.1928 In Amsterdam Sierhuis attended a trade school to be a house painter, where he gained much knowledge of materials. As an expressionist painter early in his career he focused on naturalistic landscapes. Later in the 1950's and 1960's he worked in more a abstact style. By the mid 1960's he switched from expressionism to painting human figures and more figurative themes.