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diff --git a/lists.mdwn b/lists.mdwn
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index 01dc76c7..00000000
--- a/lists.mdwn
+++ /dev/null
@@ -1,80 +0,0 @@
-(list?)
-nil
-cons
-nil?, (pair?)
-head
-tail
-
-Chris's lists:
-	nil = (t,N)  = \f. f true N
-	[a] = (f,(a,nil))
-	[b,a] = (f,(b,[a]))
-
-isnil = get-first
-head = L get-second get-first
-tail = L get-second get-second
-
-would be nice if nil tail = nil
-	nil tail = (t, N) get-second get-second = N get-second
-	so N get-second should be (t,N)
-	e.g. N = K (t,N)
-		   = (\n. K (t,n)) N
-	How to do that?
-	a fixed point g_ of g : g_ = (g g_)
-	(Y g) = g (Y g)
-	N = (\n. K (t,n)) N is of the form N = g N
-	So if we just set N = Y g, we'll have what we want. N = (Y g) = g (Y g) = g N
-	
-	i.e. N = Y g = Y (\n. K (t,n))
-	and nil = (t, N) = (t, Y (\n. K (t, n)))
-
-	nil get-second get-second ~~>
-		Y (\n. K (t, n)) get-second	~~>
-		(\n. K (t, n)) (Y (\n. K (t,n))) get-second ~~>
-		K (t, Y (\n. K (t,n))) get-second ~~>
-		(t, Y (\n. K (t,n)))
-
-
-Lists 2:
-	nil = false
-	[a] = (a,nil)
-
-L (\h\t.K deal_with_h_and_t) if-nil
-
-We've already seen enumerations: true | false, red | green | blue
-What if you want one or more of the elements to have associated data? e.g. red | green | blue <how-blue>
-
-could handle like this:
-	the-value if-red if-green (\n. handler-if-blue-to-degree-n)
-
-	then red = \r \g \b-handler. r
-		 green = \r \g \b-handler. g
-		 make-blue = \degree. \r \g \b-handler. b-handler degree
-
-A list is basically: empty | non-empty <head,tail>
-
-		empty = \non-empty-handler \if-empty. if-empty = false
-		cons = \h \t. \non-empty-handler \if-empty. non-empty-handler h t
-
-		so [a] = cons a empty = \non-empty-handler \_. non-empty-handler a empty
-
-
-
-Lists 3:
-[a; tl] isnil == (\f. f a tl) (\h \t.false) a b ~~> false a b
-
-nil isnil == (\f. M) (\h \t. false) a b ~~> M[f:=isnil] a b == a
-
-	so M could be \a \b. a, i.e. true
-	so nil = \f. true == K true == K K = \_ K
-
-	nil = K true
-	[a] = (a,nil)
-	[b,a] = (b,[a])
-
-isnil = (\x\y.false)
-
-nil tail = K true tail = true = \x\y.x = \f.f? such that f? = Kx. there is no such.
-nil head = K true head = true. could mislead.
-
-