Is it possible to define "Straight-line" logically? If it is possible, How you will define it?
42088
Is there a rigorous definition of a line?
153440
Is logical implication always determinable from just the given statements?
60436
How are symmetries precisely defined?
81676
Geodesics: Straightest or Shortest? When and Why?
57672
Trying to get all this terminology straight in logic
136359
How to define a complex function with assumptions?
147051
Soundness vs completeness, am I understanding? And proving soundness?
8986
How can a "proper" function have a vertical slope?
83119
Compass-and-straightedge construction of the square root of a given line?
135337
What does "rigorous proof" mean?
134517
Is following contradictory? Can you give an example?
100844
How should I understand "$A$ unless $B$"?
47906
Can two streamlines in a fluid be tangential to each other not crossing each other?
136658
In Harry Potter, Do Spells Travel in a Straight Line?
8094
X, Y, Z — horizontal, vertical and ...?
134199
Holomorphic function mapping a set onto a straight line
15690
Is a function defined at a single point continuous?