MyWikiBiz, Author Your Legacy — Tuesday November 11, 2025
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, 14:06, 9 December 2008
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| | The relative operator takes two propositions as arguments and reports the value "true" if the first implies the second, otherwise "false". | | The relative operator takes two propositions as arguments and reports the value "true" if the first implies the second, otherwise "false". |
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| | <center> | | <center> |
| | <math>\Upsilon \langle e, f \rangle = 1 \quad \operatorname{iff} \quad e \Rightarrow f.</math> | | <math>\Upsilon \langle e, f \rangle = 1 \quad \operatorname{iff} \quad e \Rightarrow f.</math> |
| | </center> | | </center> |
| | + | <br> |
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| | Expressing it another way, we may also write: | | Expressing it another way, we may also write: |
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| | + | <br> |
| | <center> | | <center> |
| | <math>\Upsilon \langle e, f \rangle = 1 \quad \Leftrightarrow \quad (e (f)) = 1.</math> | | <math>\Upsilon \langle e, f \rangle = 1 \quad \Leftrightarrow \quad (e (f)) = 1.</math> |
| | </center> | | </center> |
| | + | <br> |
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| | + | In writing this, however, it is important to notice that the 1's appearing on the left and right have different meanings. Filling in the details, we have: |
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| | + | <br> |
| | + | <center> |
| | + | <math>\Upsilon \langle e, f \rangle = 1 \in \mathbb{B} \quad \Leftrightarrow \quad (e (f)) = 1 : \mathbb{B}^2 \to \mathbb{B}.</math> |
| | + | </center> |
| | + | <br> |
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| | + | Finally, it is often convenient to write the first argument as a subscript, hence <math>\Upsilon_e \langle f \rangle = \Upsilon \langle e, f \rangle.</math> |
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| | ====Option 2 : More General==== | | ====Option 2 : More General==== |