On Certainty

On Certainty (German: Über Gewißheit) is a philosophical book composed from the notes written by Ludwig Wittgenstein just prior to his death. Some of the notes were left at the home of G. E. M. Anscombe, who later compiled the notes into a book.

The book's concerns are largely epistemological, its main theme being that there are some things which must be exempt from doubt in order for human practices to be possible (i.e. 'doubt' being a practice as well). The book takes as its starting point the 'here is a hand' argument made by G. E. Moore and examines the place of claims to know in our knowledge.

Another important point is his claim that all doubt is embedded into underlying beliefs and therefore that the most radical forms of doubt must be rejected since they form a contradiction within the system that expressed them. Wittgenstein also provides a novel refutation of various forms of philosophical skepticism. The book was published posthumously in 1969 from notebooks written in the last two years of his life.

Ludwig Wittgenstein

Ludwig Josef Johann Wittgenstein (/ˈvɪtɡənˌstaɪn/;German: [ˈvɪtgənˌʃtaɪn]; 26 April 1889 – 29 April 1951) was an Austrian-British philosopher who worked primarily in logic, the philosophy of mathematics, the philosophy of mind, and the philosophy of language. From 1929 to 1947, Wittgenstein taught at the University of Cambridge. During his lifetime he published just one slim book, the 75-page Tractatus Logico-Philosophicus (1921), one article, one book review and a children's dictionary. His voluminous manuscripts were edited and published posthumously. Philosophical Investigations appeared as a book in 1953, and has since come to be recognised as one of the most important works of philosophy in the twentieth century. His teacher Bertrand Russell described Wittgenstein as "the most perfect example I have ever known of genius as traditionally conceived; passionate, profound, intense, and dominating."

Born in Vienna into one of Europe's richest families, he inherited a large fortune from his father in 1913. He gave some considerable sums to poor artists. In a period of severe personal depression after the first World War, he then gave away his entire fortune to his brothers and sisters. Three of his brothers committed suicide, with Wittgenstein contemplating it too. He left academia several times—serving as an officer on the front line during World War I, where he was decorated a number of times for his courage; teaching in schools in remote Austrian villages where he encountered controversy for hitting children when they made mistakes in mathematics; and working as a hospital porter during World War II in London where he told patients not to take the drugs they were prescribed while largely managing to keep secret the fact that he was one of the world's most famous philosophers. He described philosophy, however, as "the only work that gives me real satisfaction."

Tony Robbins

Tony Robbins (born Anthony J. Mahavoric; February 29, 1960) is an American motivational speaker, personal finance instructor, and self-help author. He became well known from his infomercials and self-help books: Unlimited Power, Unleash the Power Within and Awaken the Giant Within.

In 2007, he was named in Forbes magazine's "Celebrity 100" list.Forbes estimated that Robbins earned approximately US$30 million in that year.

Early life

Robbins was born Anthony J. Mahavoric in North Hollywood, California, on February 29, 1960. Robbins is the eldest of three children and his parents divorced when he was 7. His mother then had a series of husbands, including Jim Robbins, a former semiprofessional baseball player who legally adopted Anthony when he was 12.

His father could not provide for their family, so he left them. His mother started abusing alcohol and prescription drugs sometime after. While growing up, Robbins was a primary care-giver, and helped provide for his siblings. Robbins was raised in Azusa and Glendora, California, and attended Glendora High School. He was elected student body president in his senior year, and grew 10 inches in high school, a growth spurt later attributed to a pituitary tumor. He has said his home life was "chaotic" and "abusive". When he was 17 years old, Robbins' mother chased him out of the house with a knife, and he never returned. Robbins later worked as a janitor, and did not attend college.