Leon Albert Henkin (1921 – 2006) was a logician who is principally known for "Henkin's completeness proof". It is his version of the proof of the semantic completeness of standard systems of first-order logic.
Kurt Gödel had already proved that in 1929. Henkin proved it in 1949 and since his proof is much easier to survey than Gödel's, it has become the standard choice of completeness proof for presentation in introductory classes and texts. Henkin's proof is an existence proof. While it guarantees that if a sentence α follows (semantically) from a set of sentences Σ, then there is a proof of α from Σ, it doesn't give that proof however. Sources: Leon Henkin. (n.d.). Retrieved December 26, 2014, from http://en.wikipedia.org/wiki/Leon_Henkin 11.09.2006 - Leon Henkin, advocate for diversity in math & science, has died. (n.d.). Retrieved December 26, 2014, from http://berkeley.edu/news/media/releases/2006/11/09_henkin.shtml
0 Comments
Gunther S. Stent (1924 – 2008) was a bacteriophage biologists, known for his studies on the metabolism of bacteria and neurobiology of leeches as well as for his writing on the history and philosophy of biology. Source: Gunther Stent. (n.d.). Retrieved December 26, 2014, from http://en.wikipedia.org/wiki/Gunther_Stent Albert Lester Lehninger (1917 –1986) was a biochemist specialized in the field of bioenergetics. Like, Stent he was studied metabolism and he has made fundamental contributions to our molecular level understanding of it.
Source: Albert L. Lehninger. (n.d.). Retrieved December 26, 2014, from http://en.wikipedia.org/wiki/Albert_L._Lehninger Rene Magritte (1898 – 1967) is renowned for thought-provoking surreal images. His paintings challenged their observers' preconditioned perceptions of reality. His first paintings were impressionistic in style. That is to say they include small and thick brush strokes, open composition, accurate depiction of light in its changing qualities (often representing the effects of time) and its reflection from objects, inclusion of movement as a crucial element of human perception and experience, and unusual visual angles. His paintings were then influenced by futurism which is an artistic and social movement that emphasized themes associated with concepts of the future, including speed, technology, youth and violence, cars and the industrial city. He worked as a poster and advertisement designer in a wallpaper factory then he became a full-time painter upon signing a contract with Galerie 'Le Centaure' in Brussels. Magritte produced his first surreal painting, The Lost Jockey (Le jockey perdu) shown bellow. A year later, he held his first exhibition in Brussels in 1927 after which he left his native Belgium and became a leading member of the movement. Source: René Magritte. (n.d.). Retrieved December 26, 2014, from http://en.wikipedia.org/wiki/René_Magritte The Lovers: Magritte's mother committed suicide by drowning herself in the River Sambre. According to a legend, 13-year-old Magritte was present when her body was retrieved from the water. Her dress was covering her face, an image that has been suggested as the source of several of Magritte's paintings in 1927–1928 of people with cloth obscuring their faces. http://en.wikipedia.org/wiki/Ren%C3%A9_Magritte |