Again, some traditional mathematicians have problems to understand that if the considered point is defined by two coordinates, so is the case about the set of all points that are at the same distance,
r, from that fixed point, or in other words, all the considered points are on the same plane in any possible system, in order to be considered as a circle by Traditional Mathematics.
So again, here is an example of verbal_symbolic-only reasoning.
Definition of Circle
Definition: A circle is the set of all points on a given plane that are at the same distance,
r, from a fixed point.
General (Cartesian) equation:
X2 +
Y2 =
r2 where
r is the radius (it is general in the sense that we care only about the fact that the set of the considered points are on the same plane, no matter what is the exact position of the circle on the considered plane including the center point (which by this equation is 0,0 but this fact is insignificant to the considered argument)).
Some traditional mathematicians here still try to avoid the considered argument by claiming that (
X-a)
2 + (
Y-b)
2 =
r2 (where (
a,b) is the position of the center point on the considered plane) is significant to the considered argument, but their twisted maneuvers have no influence on the validity of the considered argument.
So once again, according to this verbal_symbolic-only reasoning (with or without all these twisted maneuvers), we still have a circle even if
r=0 or
r=∞, which is simply nonsense.
By using also visual_spatial brain skills, one easily understands that 0 =
X2 +
Y2 is the indivisible local building-block (0-dimensional space, in this case) and ∞ =
X2 +
Y2 is the indivisible non-local building-block (1-dimensional space, in this case), that if associated they provide a given circle (where the position of that circle on a given plane has no influence on the validity of the considered argument).
So once again,
http://www.internationalskeptics.com/forums/showpost.php?p=8686803&postcount=2032.