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.
Modern republicanism is the guiding political philosophy of the United States. It has been a major part of American civic thought since its founding. It stresses liberty and unalienable individual rights as central values, making people sovereign as a whole, rejects monarchy, aristocracy and inherited political power, expects citizens to be independent in their performance of civic duties, and vilifies corruption.