In three experiments, the relation between different modes of thought and the generation of “creative” and original ideas was investigated. Participants were asked to generate items according to a specific instruction . They either did so immediately after receiving the instruction, or after a few minutes of conscious thought, or after a few minutes of distraction during which “unconscious thought” was hypothesized to take place. Throughout the experiments, the items participants listed under “unconscious thought” conditions were more original. It was (...) concluded that whereas conscious thought may be focused and convergent, unconscious thought may be more associative and divergent. (shrink)

Journal of Experimental Social Psychology, 44, 2-9.

Snell's law of refraction did not affect the study of optics until twenty‐five years after its publication in 1637 and by then its universality threatened to break down already. Two optical phenomena—colour dispersion and strange refraction—were discovered that did not conform to the sine law. In the early 1670s, Isaac Newton and Christiaan Huygens respectively investigated these phenomena. They tried to describe the irregular behaviour of light rays mathematically and to reconcile it with ordinary refraction. This paper discusses their investigations (...) and aims at throwing new light on the history of seventeenth‐century optics. Both initially approached the problem in a mathematical way in which they built on Descartes' analysis of refraction. This is surprising because it contradicts their earlier dismissal of Descartes' account and it does not fit our picture of them as mathematical physicists. By looking more closely at their early investigations it becomes clear that Newton and Huygens first had to develop the approach to optics of their later writings. After Descartes placed the issue of the physical nature of light rays on the scientific agenda in 1637, they recognized its purport in their struggles with colour dispersion and strange refraction. It was at this point that their physical optics evolved from the traditional geometrical optics with which they had started. (shrink)

Isaac Beeckman was a master craftsman from the Zeeland town Middelburg who studied to become schoolmaster in the Holland towns of Rotterdam and Dordrecht. He was a strict Calvinist and a tireless observer and contemplator of natural phenomena. Foremost, he was the first mechanical philosopher in Europe who played a key role in the intellectual development of René Descartes and inspired pioneers of mechanistic thinking Marin Mersenne and Pierre Gassendi . We know this because Beeckman kept a journal throughout his (...) life in which he recorded his observations and ideas. The journal is a treasure trove of early modern knowing. Beeckman had a keen eye for the world around him and responded to what he saw, as well as the reflections of others, with a highly original mind. The journal was discovered in 1905 by Cornelis de Waard , who subsequently edited and published it between 1939 and 1953 . Although some acquainta .. (shrink)