1989 Tiananmen Square protests and massacre

Liu Xiaobo

Liu Xiaobo (Chinese: 刘晓波; pinyin: Liú Xiǎobō; 28 December 1955 – 13 July 2017) was a Chinese literary critic, human rights activist, philosopher and Nobel Peace Prize laureate who called for political reforms and was involved in campaigns to end Chinese Communist Party one-party rule in China.

Source: Wikipedia · CC BY-SA 4.0

Leonardo da Vinci

Leonardo di ser Piero da Vinci (15 April 1452 – 2 May 1519) was an Italian polymath of the High Renaissance who was active as a painter, draughtsman, engineer, scientist, theorist, sculptor, and architect.

Source: Wikipedia · CC BY-SA 4.0

Photo: Attributed to Francesco Melzi · Public domain

Abraham Lincoln

16th President of the United States who led the nation through the Civil War and abolished slavery.

Photo: Alexander Gardner · Public domain

Jean-Paul Sartre

Jean-Paul Charles Aymard Sartre (US also; French:; 21 June 1905 – 15 April 1980) was a French philosopher, political activist, and writer, considered a leading figure in 20th-century French philosophy and Marxism.

Source: Wikipedia · CC BY-SA 4.0

Photo: Moshe Milner · CC BY-SA 3.0

Leonhard Euler

Leonhard Euler ( OY-lər; 15 April 1707 – 18 September 1783) was a Swiss polymath who was active as a mathematician, physicist, astronomer, logician, geographer, music theorist and engineer.

Source: Wikipedia · CC BY-SA 4.0

Photo: Jakob Emanuel Handmann · Public domain