Quote : A line can be described as an ideal zero-width,infinitely long, perfectly straight curve (the term curve in mathematics includes "straight curves")containing an infinite number of points. In Euclidean geometry, exactly one line can be found that passes through any two points. The line provides the shortest connection between the points.
In two dimensions, two different lines can either be parallel, meaning they never meet, or may intersect at one and only one point. In three or more dimensions, lines may also be skew, meaning they don't meet, but also don't define a plane.
Two distinct planes intersect in at most one line. Three or more points that lie on the same line are called collinear.
I have the faint idea that there is something fishy with your examples.
The line of a falling heavy object may be a straight line (there may be factors to disturb this ); it is an abstraction. I mean perfect straight lines, like in the
mathematical sense. A cleavage in stones and minerals is never pure straight when not manipulated by men. Light? Abstraction?
The line, idea of lines fascinates me. I think management of fire, the 'invention', materializing of the idea of the straight line and the invention of the wheel are about it.
(yea, loads of other things followed and tons of exemples in between and I know I'm a fool) but....
Anyway , most of what we see as lines are not really lines at all
but contours or the intersection of planes. Even the thinnest wire is a minuscule cilinder.
Last edited by BranShea; 08/21/2008 5:09 PM.
