When people dream, they often are not aware of the fact that the experiences they are having exist only in their minds. It is precisely this phenomenon that has given rise to the dream argument, a philosophical postulation that contends that our senses, on which we rely to distinguish reality from illusion, cannot be fully trusted. Both Plato and Descartes, among other prominent philosophers, expounded on this topic. What successful film trilogy is based on this premise?
Henry David Thoreau
Back in the day
In 1961, 23 days after Soviet cosmonaut Yuri Gagarin became the first human to orbit Earth, astronaut Alan Shepard became the first American to be launched into space. Shepard's suborbital flight—part of the US space program Project Mercury—reached a height of 115 miles (185 km). He performed several maneuvers of his capsule, Freedom 7, but returned after only a 15-minute flight. Although Gagarin was the first human in space, Shepard was the first to return in what way?
Born on a day like today
The third son of Maria Theresa and Holy Roman Emperor Francis I, Leopold II succeeded his father as duke of Tuscany in 1765 and his brother as emperor and ruler of the Hapsburg lands in 1790. A practitioner of what has been termed enlightened despotism, Leopold is remembered as a ruler of outstanding diplomatic and administrative abilities. He was emperor for just two years, but in that time, he precipitated the decade-long French Revolutionary Wars by making an alliance with what power?