X-Git-Url: http://lambda.jimpryor.net/git/gitweb.cgi?p=lambda.git;a=blobdiff_plain;f=test2.mdwn;fp=test2.mdwn;h=58a2a03f5609138cfbd0f38e7772b03af742e793;hp=1ac561a5becd0a38affef1c7817c6b8e933477d0;hb=50310689cd104b8cbabc3ac3bb621b1086fcdd3c;hpb=f7a2d25e83e11943a2be9b40dbce31b40ca0d66f;ds=sidebyside diff --git a/test2.mdwn b/test2.mdwn index 1ac561a5..58a2a03f 100644 --- a/test2.mdwn +++ b/test2.mdwn @@ -285,18 +285,16 @@ It's possible to enhance the lambda calculus so that functions do get identified It's often said that dynamic systems are distinguished because they are the ones in which **order matters**. However, there are many ways in which order can matter. If we have a trivalent boolean system, for example---easily had in a purely functional calculus---we might choose to give a truth-table like this for "and": -
-true and true = true
-true and true = true
-true and * = *
-true and false = false
-* and true = *
-* and * = *
-* and false = *
-false and true = false
-false and * = false
-false and false = false
-
+ true and true = true
+ true and true = true
+ true and * = *
+ true and false = false
+ * and true = *
+ * and * = *
+ * and false = *
+ false and true = false
+ false and * = false
+ false and false = false
And then we'd notice that `* and false` has a different intepretation than `false and *`. (The same phenomenon is already present with the material conditional in bivalent logics; but seeing that a non-symmetric semantics for `and` is available even for functional languages is instructive.)