Édouard Manet (1832 – 1883), was a French painter. He was one of the first 19th-century artists to paint modern life, and a pivotal figure in the transition from Realism to Impressionism.
The notion of line or straight line was introduced by ancient mathematicians to represent straight objects (i.e., having no curvature) with negligible width and depth. Lines are an idealization of such objects.
Until the seventeenth century, lines were defined like this: “The [straight or curved] line is the first species of quantity, which has only one dimension, namely length, without any width nor depth, and is nothing else than the flow or run of the point which […] will leave from its imaginary moving some vestige in length, exempt of any width. […] The straight line is that which is equally extended between its points”
Euclid described a line as “breadthless length” which “lies equally with respect to the points on itself”.
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