Is Every Asymmetric Relation Also Antisymmetric?

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SUMMARY

The discussion centers on the relationship between asymmetric and antisymmetric relations in logic, specifically questioning the assertion that if a relation R is asymmetric, then it is also antisymmetric. The example of the less-than relation (<) is used to illustrate that for natural numbers, the conditions of asymmetry do not imply antisymmetry, as shown by the contradiction arising from the statement 1 < x and x < 1. The conclusion drawn is that the definitions of "asymmetric" and "antisymmetric" must be clearly stated to understand this relationship.

PREREQUISITES
  • Understanding of basic set theory concepts
  • Familiarity with the definitions of asymmetric and antisymmetric relations
  • Knowledge of logical reasoning and proof techniques
  • Basic understanding of natural numbers and their properties
NEXT STEPS
  • Study the formal definitions of asymmetric and antisymmetric relations in set theory
  • Explore examples of relations that are asymmetric but not antisymmetric
  • Learn about other types of relations, such as symmetric and reflexive
  • Investigate the implications of these properties in mathematical proofs and logic
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Students of mathematics, logicians, and anyone interested in the foundational concepts of relations in set theory and logic.

icantadd
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I ran across the following statement, in a tutorial on logic,

If R is an asymmetric relation then R is antisymmetric.

Perhaps, the above is true. I will attempt to argue it is not. Okay, then suppose R really is asymmetric, for example the relation (<) So for an arbitrary (c,d) c < d then d >= c. From this we should get R is antisymmetric. It R is antisymmetric though, ( c < d and d < c then d = c )

Take for example the natural numbers, suppose 1. 1 < x and x < 1 means 1 = x. Which would mean that 1 is less than 1, and 1 is greater than 1, which poses contradiction because 1 is not less than 1.
 
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c<d and d<c certainly does not imply c=d. It is impossible for c<d and d<c to be simultaneously satisfied.
 
icantadd said:
I ran across the following statement, in a tutorial on logic,

If R is an asymmetric relation then R is antisymmetric.

Perhaps, the above is true. I will attempt to argue it is not. Okay, then suppose R really is asymmetric, for example the relation (<) So for an arbitrary (c,d) c < d then d >= c. From this we should get R is antisymmetric. It R is antisymmetric though, ( c < d and d < c then d = c )

Take for example the natural numbers, suppose 1. 1 < x and x < 1 means 1 = x. Which would mean that 1 is less than 1, and 1 is greater than 1, which poses contradiction because 1 is not less than 1.
The first thing you should do is state the definitions, as given in that tutorial, of "asymmetric" and "antisymmetric".
 

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