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In (1) we consider the effects of each <math>x\!</math> in its practical bearing on contexts of the form <math>(\underline{~~}, y),</math> as <math>y\!</math> ranges over <math>G,\!</math> and the effects are such that <math>x\!</math> takes <math>(\underline{~~}, y)</math> into <math>x \cdot y,</math> for <math>y\!</math> in <math>G,\!</math> all of which is notated as <math>x = \{ (y : x \cdot y) ~|~ y \in G \}.</math>  The pairs <math>(y : x \cdot y)</math> can be found by picking an <math>x\!</math> from the left margin of the group operation table and considering its effects on each <math>y\!</math> in turn as these run across the top margin.  This aspect of pragmatic definition we recognize as the regular ante-representation:
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In (1) we consider the effects of each <math>x\!</math> in its practical bearing on contexts of the form <math>(\underline{~~}, y),</math> as <math>y\!</math> ranges over <math>G,\!</math> and the effects are such that <math>x\!</math> takes <math>(\underline{~~}, y)</math> into <math>x \cdot y,</math> for <math>y\!</math> in <math>G,\!</math> all of which is notated as <math>x = \{ (y : x \cdot y) ~|~ y \in G \}.</math>  The pairs <math>(y : x \cdot y)</math> can be found by picking an <math>x\!</math> from the left margin of the group operation table and considering its effects on each <math>y\!</math> in turn as these run across the top margin.  This aspect of pragmatic definition we recognize as the regular ante-representation:
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<pre>
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{| align="center" cellpadding="6" width="90%"
    e = e:e + f:f + g:g + h:h
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| align="center" |
 
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<math>\begin{matrix}
    f = e:f + f:e + g:h + h:g
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\mathrm{e}
 
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& = & \mathrm{e}:\mathrm{e}
    g = e:g + f:h + g:e + h:f
+
& + & \mathrm{f}:\mathrm{f}
 
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& + & \mathrm{g}:\mathrm{g}
    h = e:h + f:g + g:f + h:e
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& + & \mathrm{h}:\mathrm{h}
</pre>
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\\[4pt]
 +
\mathrm{f}
 +
& = & \mathrm{e}:\mathrm{f}
 +
& + & \mathrm{f}:\mathrm{e}
 +
& + & \mathrm{g}:\mathrm{h}
 +
& + & \mathrm{h}:\mathrm{g}
 +
\\[4pt]
 +
\mathrm{g}
 +
& = & \mathrm{e}:\mathrm{g}
 +
& + & \mathrm{f}:\mathrm{h}
 +
& + & \mathrm{g}:\mathrm{e}
 +
& + & \mathrm{h}:\mathrm{f}
 +
\\[4pt]
 +
\mathrm{h}
 +
& = & \mathrm{e}:\mathrm{h}
 +
& + & \mathrm{f}:\mathrm{g}
 +
& + & \mathrm{g}:\mathrm{f}
 +
& + & \mathrm{h}:\mathrm{e}
 +
\end{matrix}</math>
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|}
    
In (2) we consider the effects of each <math>x\!</math> in its practical bearing on contexts of the form <math>(y, \underline{~~}),</math> as <math>y\!</math> ranges over <math>G,\!</math> and the effects are such that <math>x\!</math> takes <math>(y, \underline{~~})</math> into <math>y \cdot x,</math> for <math>y\!</math> in <math>G,\!</math> all of which is notated as <math>x = \{ (y : y \cdot x) ~|~ y \in G \}.</math>  The pairs <math>(y : y \cdot x)</math> can be found by picking an <math>x\!</math> from the top margin of the group operation table and considering its effects on each <math>y\!</math> in turn as these run down the left margin.  This aspect of pragmatic definition we recognize as the regular post-representation:
 
In (2) we consider the effects of each <math>x\!</math> in its practical bearing on contexts of the form <math>(y, \underline{~~}),</math> as <math>y\!</math> ranges over <math>G,\!</math> and the effects are such that <math>x\!</math> takes <math>(y, \underline{~~})</math> into <math>y \cdot x,</math> for <math>y\!</math> in <math>G,\!</math> all of which is notated as <math>x = \{ (y : y \cdot x) ~|~ y \in G \}.</math>  The pairs <math>(y : y \cdot x)</math> can be found by picking an <math>x\!</math> from the top margin of the group operation table and considering its effects on each <math>y\!</math> in turn as these run down the left margin.  This aspect of pragmatic definition we recognize as the regular post-representation:
   −
<pre>
+
{| align="center" cellpadding="6" width="90%"
    e = e:e + f:f + g:g + h:h
+
| align="center" |
 
+
<math>\begin{matrix}
    f = e:f + f:e + g:h + h:g
+
\mathrm{e}
 
+
& = & \mathrm{e}:\mathrm{e}
    g = e:g + f:h + g:e + h:f
+
& + & \mathrm{f}:\mathrm{f}
 
+
& + & \mathrm{g}:\mathrm{g}
    h = e:h + f:g + g:f + h:e
+
& + & \mathrm{h}:\mathrm{h}
</pre>
+
\\[4pt]
 +
\mathrm{f}
 +
& = & \mathrm{e}:\mathrm{f}
 +
& + & \mathrm{f}:\mathrm{e}
 +
& + & \mathrm{g}:\mathrm{h}
 +
& + & \mathrm{h}:\mathrm{g}
 +
\\[4pt]
 +
\mathrm{g}
 +
& = & \mathrm{e}:\mathrm{g}
 +
& + & \mathrm{f}:\mathrm{h}
 +
& + & \mathrm{g}:\mathrm{e}
 +
& + & \mathrm{h}:\mathrm{f}
 +
\\[4pt]
 +
\mathrm{h}
 +
& = & \mathrm{e}:\mathrm{h}
 +
& + & \mathrm{f}:\mathrm{g}
 +
& + & \mathrm{g}:\mathrm{f}
 +
& + & \mathrm{h}:\mathrm{e}
 +
\end{matrix}</math>
 +
|}
    
If the ante-rep looks the same as the post-rep, now that I'm writing them in the same dialect, that is because <math>V_4\!</math> is abelian (commutative), and so the two representations have the very same effects on each point of their bearing.
 
If the ante-rep looks the same as the post-rep, now that I'm writing them in the same dialect, that is because <math>V_4\!</math> is abelian (commutative), and so the two representations have the very same effects on each point of their bearing.
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