X-Git-Url: http://lambda.jimpryor.net/git/gitweb.cgi?p=lambda.git;a=blobdiff_plain;f=week1.mdwn;h=1bc2309e1e9c79eea7118b9f6e72045a90b3317d;hp=b4d584d4f7db1676ab42891b9e32f3d5980599f6;hb=c86596d41ed6ca32fff882b468eade84bc13fb07;hpb=1a4c40836dc37109b086d47ee9fb27c2f9726e6b

diff --git a/week1.mdwn b/week1.mdwn
index b4d584d4..1bc2309e 100644
--- a/week1.mdwn
+++ b/week1.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":
 
-<pre><code>
-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
-</code></pre>
+	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.)
 
@@ -673,11 +671,8 @@ Here's how it looks to say the same thing in various of these languages.
 
 	and there's no more mutation going on there than there is in:
 
-	<!--
-	<pre>
-	<code>&forall;x. (F x or &forall;x (not (F x)))</code>
-	</pre>
-	-->
+	<pre><code>&forall;x. (F x or &forall;x (not (F x)))
+	</code></pre>
 
 	When a previously-bound variable is rebound in the way we see here, that's called **shadowing**: the outer binding is shadowed during the scope of the inner binding.