X-Git-Url: http://lambda.jimpryor.net/git/gitweb.cgi?p=lambda.git;a=blobdiff_plain;f=week4.mdwn;h=61033f5602f114fcbc33eb8ea03e6949733f3907;hp=e6bab7a1d8aafb2d4d70d0620851fe074e09da0d;hb=bfc18dfc2a8f9fee385b4f6f2b31fc99c155c728;hpb=ec55bd71ab1beda4348105a40324947d8753f4e3

diff --git a/week4.mdwn b/week4.mdwn
index e6bab7a1..61033f56 100644
--- a/week4.mdwn
+++ b/week4.mdwn
@@ -1,9 +1,6 @@
 [[!toc]]
 
-#These notes return to the topic of fixed point combiantors for one more return to the topic of fixed point combinators#
-
-#Q: How do you know that every term in the untyped lambda calculus has
-a fixed point?#
+#Q: How do you know that every term in the untyped lambda calculus has a fixed point?#
 
 A: That's easy: let `T` be an arbitrary term in the lambda calculus.  If
 `T` has a fixed point, then there exists some `X` such that `X <~~>
@@ -171,3 +168,8 @@ so A 4 x is to A 3 x as hyper-exponentiation is to exponentiation...
 
 *    What *exactly* is primitive recursion?
 
+*    I hear that `Y` delivers the *least* fixed point.  Least
+     according to what ordering?  How do you know it's least?
+     Is leastness important?
+
+