Prove a point exists

[itinerant1]

A tree is not an abstraction. While the word that we assign to the object is tree, the object is there not not an abstraction. If someone had a different name for what we call tree (which does happen as other languages call it something other than tree) that does not change the object in any way.

The concept or idea that the word “tree” corresponds to is an abstraction. It is a universal, “treeness”, and denotes all plants classified as a tree.

The tree in the wood is a particular physical thing, as is our sense perception of it, and the image we may form in the mind, as well. Percepts differ from concepts in the former are particular and the latter are universal or abstract.

Perhaps your interlocutor intended “tree” the concept or mental word. Hopefully he will clarify, but I thought I would volunteer my 2 cents worth.

 

[yppop]

I took a course in college many years ago. We discussed this topic for a week. Can you prove that a point exists.

Eucharisteo
Sorry for joining this thread so late, I hope I am not repeating what someone else may have contributed, but in reference to your original request, I cannot give you a definitive answer, I have never seen a specifically direct proof of the existence of a point, but I offer the following for consideration:

1. You may want to look into Richard Dedekind’s solution for the continuity of the real number line. He defines the irrational numbers using the rational numbers and shows that a point exists for a continuous line no matter where you intersect it. The proof is rather long but rigorous. And it assumes that for every point in space there is a number and even more so for every number there is a point.
2. Rene Descartes showed that if you move a straight vertical line, that intersects a circle at two points, along the horizontal axis, the intersecting points will approach one another along the circumference until they reach a limit at a point where the line forms a tangent with the circle.
3. William Kingdon Clifford uses a simple glass of water, which consists of three solids: water, air, and glass, to argue that the boundary between solids is a surface; the boundary between surfaces is a line, and if you color on half the glass blue and the other half red you can see that the boundary (the line bounding water, air and glass) of a line is a point.

I hope this might help you.

Yppop

 

[JDaniel]

You know, I’ve read a few forums where I defy you prove that *any *point exists…

Really?

jd