Black DeathThe Black Death (also known as the Pestilence, the Great Mortality or the Plague) was a bubonic plague pandemic occurring in Western Eurasia and North Africa from 1346 to 1353. It is the most fatal pandemic recorded in human history, causing the deaths of 75–200 million people, peaking in Europe from 1347 to 1351. Bubonic plague is caused by the bacterium Yersinia pestis spread by fleas, but during the Black Death it probably also took a secondary form, spread by person-to-person contact via aerosols, causing pneumonic plague.
Equal temperamentAn equal temperament is a musical temperament or tuning system that approximates just intervals by dividing an octave (or other interval) into equal steps. This means the ratio of the frequencies of any adjacent pair of notes is the same, which gives an equal perceived step size, as pitch is perceived roughly as the logarithm of frequency.
Contemporary philosophyContemporary philosophy is the present period in the history of Western philosophy beginning at the early 20th century with the increasing professionalization of the discipline and the rise of analytic and continental philosophy. The phrase "contemporary philosophy" is a piece of technical terminology in philosophy that refers to a specific period in the history of Western philosophy (namely the philosophy of the 20th and 21st centuries).
