Snellen defined standard vision as the ability to recognise a letter (âoptotypeâ) when it forms an angle of 5 arcminutes, which is âline nineâ of the letters (âoptotypesâ) on the chart at 6 metres. Hermann, Dutch ophthalmologist, 1834-1908.
In the context of the theory of Marxist revolutionary struggle, vanguardism is a strategy whereby the most class-conscious and politically advanced sections of the proletariat or working class, described as the revolutionary vanguard, form organizations in order to draw larger sections of the working class towards revolutionary politics and serve as manifestations of proletarian political power against its class enemies.
Eduard Bernstein, early revisionist. Within the Marxist movement, the word revisionism is used to refer to various ideas, principles and theories that are based on a significant revision of fundamental Marxist premises.