Oliver Wilhelm, Ph.D., is Professor of Psychology at Humboldt-University Berlin, Germany. He earned his doctoral degree in 2000 from the Universeity of Mannheim and subsequently worked at the Georgia Institute of Technology, Atlanta, and at the University of Arizona in Tucson. His research focuses on individual differences in working memory, reasoning, and mental speed. Additional research interests are in intellectual engagement, openness for new experiences, and cognitive failures and how these traits relate to various abilities. He is also doing experimental work on deductive reasoning and