diff --git a/library/data/pnat.lean b/library/data/pnat.lean
index e1846eff1..56f1563cd 100644
--- a/library/data/pnat.lean
+++ b/library/data/pnat.lean
@@ -13,7 +13,7 @@ are those needed for that construction.
 import data.rat.order data.nat
 open nat rat
 
-section pnat
+namespace pnat
 
 inductive pnat : Type :=
   pos : Π n : nat, n > 0 → pnat
@@ -62,7 +62,7 @@ definition pnat_lt_decidable [instance] {p q : pnat} : decidable (p < q) :=
   pnat.rec_on p (λ n H, pnat.rec_on q
     (λ m H2, if Hl : n < m then decidable.inl Hl else decidable.inr Hl))
 
-theorem ple.trans {p q r : pnat} (H1 : p ≤ q) (H2 : q ≤ r) : p ≤ r := nat.le.trans H1 H2
+theorem le.trans {p q r : pnat} (H1 : p ≤ q) (H2 : q ≤ r) : p ≤ r := nat.le.trans H1 H2
 
 definition max (p q : pnat) :=
   pnat.pos (nat.max (p~) (q~)) (nat.lt_of_lt_of_le (!nat_of_pnat_pos) (!le_max_right))
@@ -79,35 +79,35 @@ theorem max_eq_left {a b : ℕ+} (H : ¬ a < b) : max a b = a :=
   have Hnat : nat.max a~ b~ = a~, from nat.max_eq_left H,
   pnat.eq Hnat
 
-theorem pnat.le_of_lt {a b : ℕ+} (H : a < b) : a ≤ b := nat.le_of_lt H
+theorem le_of_lt {a b : ℕ+} (H : a < b) : a ≤ b := nat.le_of_lt H
 
-theorem pnat.not_lt_of_le {a b : ℕ+} (H : a ≤ b) : ¬ (b < a) := nat.not_lt_of_ge H
+theorem not_lt_of_ge {a b : ℕ+} (H : a ≤ b) : ¬ (b < a) := nat.not_lt_of_ge H
 
-theorem pnat.le_of_not_lt {a b : ℕ+} (H : ¬ a < b) : b ≤ a := nat.le_of_not_gt H
+theorem le_of_not_gt {a b : ℕ+} (H : ¬ a < b) : b ≤ a := nat.le_of_not_gt H
 
-theorem pnat.eq_of_le_of_ge {a b : ℕ+} (H1 : a ≤ b) (H2 : b ≤ a) : a = b :=
+theorem eq_of_le_of_ge {a b : ℕ+} (H1 : a ≤ b) (H2 : b ≤ a) : a = b :=
   pnat.eq (nat.eq_of_le_of_ge H1 H2)
 
-theorem pnat.le.refl (a : ℕ+) : a ≤ a := !nat.le.refl
+theorem le.refl (a : ℕ+) : a ≤ a := !nat.le.refl
 
 notation 2 := pnat.pos 2 dec_trivial
 notation 3 := pnat.pos 3 dec_trivial
 definition pone : pnat := pnat.pos 1 dec_trivial
 
-definition pnat.to_rat [reducible] (n : ℕ+) : ℚ :=
+definition rat_of_pnat [reducible] (n : ℕ+) : ℚ :=
   pnat.rec_on n (λ n H, of_nat n)
 
-theorem pnat.to_rat_of_nat (n : ℕ+) : pnat.to_rat n = of_nat n~ :=
+theorem pnat.to_rat_of_nat (n : ℕ+) : rat_of_pnat n = of_nat n~ :=
   pnat.rec_on n (λ n H, rfl)
 
 -- these will come in rat
 
 theorem rat_of_nat_nonneg (n : ℕ) : 0 ≤ of_nat n := trivial
 
-theorem rat_of_pnat_ge_one (n : ℕ+) : pnat.to_rat n ≥ 1 :=
+theorem rat_of_pnat_ge_one (n : ℕ+) : rat_of_pnat n ≥ 1 :=
   pnat.rec_on n (λ m h, (iff.mp' !of_nat_le_of_nat) (succ_le_of_lt h))
 
-theorem rat_of_pnat_is_pos (n : ℕ+) : pnat.to_rat n > 0 :=
+theorem rat_of_pnat_is_pos (n : ℕ+) : rat_of_pnat n > 0 :=
   pnat.rec_on n (λ m h, (iff.mp' !of_nat_pos) h)
 
 theorem of_nat_le_of_nat_of_le {m n : ℕ} (H : m ≤ n) : of_nat m ≤ of_nat n :=
@@ -116,25 +116,25 @@ theorem of_nat_le_of_nat_of_le {m n : ℕ} (H : m ≤ n) : of_nat m ≤ of_nat n
 theorem of_nat_lt_of_nat_of_lt {m n : ℕ} (H : m < n) : of_nat m < of_nat n :=
   (iff.mp' !of_nat_lt_of_nat) H
 
-theorem pnat_le_to_rat_le {m n : ℕ+} (H : m ≤ n) : pnat.to_rat m ≤ pnat.to_rat n :=
+theorem rat_of_pnat_le_of_pnat_le {m n : ℕ+} (H : m ≤ n) : rat_of_pnat m ≤ rat_of_pnat n :=
   begin
     rewrite *pnat.to_rat_of_nat,
     apply of_nat_le_of_nat_of_le H
   end
 
-theorem pnat_lt_to_rat_lt {m n : ℕ+} (H : m < n) : pnat.to_rat m < pnat.to_rat n :=
+theorem rat_of_pnat_lt_of_pnat_lt {m n : ℕ+} (H : m < n) : rat_of_pnat m < rat_of_pnat n :=
   begin
     rewrite *pnat.to_rat_of_nat,
     apply of_nat_lt_of_nat_of_lt H
   end
 
-theorem rat_le_to_pnat_le {m n : ℕ+} (H : pnat.to_rat m ≤ pnat.to_rat n) : m ≤ n :=
+theorem pnat_le_of_rat_of_pnat_le {m n : ℕ+} (H : rat_of_pnat m ≤ rat_of_pnat n) : m ≤ n :=
   begin
     rewrite *pnat.to_rat_of_nat at H,
     apply (iff.mp !of_nat_le_of_nat) H
   end
 
-definition inv (n : ℕ+) : ℚ := (1 : ℚ) / pnat.to_rat n
+definition inv (n : ℕ+) : ℚ := (1 : ℚ) / rat_of_pnat n
 postfix `⁻¹` := inv
 
 theorem inv_pos (n : ℕ+) : n⁻¹ > 0 := div_pos_of_pos !rat_of_pnat_is_pos
@@ -165,9 +165,7 @@ theorem add_invs_nonneg (m n : ℕ+) : 0 ≤ m⁻¹ + n⁻¹ :=
     repeat apply inv_pos
   end
 
-set_option pp.coercions true
-
-theorem pnat_one_mul (n : ℕ+) : pone * n = n :=
+theorem one_mul (n : ℕ+) : pone * n = n :=
   begin
     apply pnat.eq,
     rewrite [↑pone, ↑mul, ↑nat_of_pnat, one_mul]
@@ -176,19 +174,19 @@ theorem pnat_one_mul (n : ℕ+) : pone * n = n :=
 theorem pone_le (n : ℕ+) : pone ≤ n :=
   succ_le_of_lt (nat_of_pnat_pos n)
 
-theorem pnat_to_rat_mul (a b : ℕ+) : pnat.to_rat (a * b) = pnat.to_rat a * pnat.to_rat b :=
+theorem pnat_to_rat_mul (a b : ℕ+) : rat_of_pnat (a * b) = rat_of_pnat a * rat_of_pnat b :=
   by rewrite *pnat.to_rat_of_nat
 
 theorem mul_lt_mul_left (a b c : ℕ+) (H : a < b) : a * c < b * c :=
    nat.mul_lt_mul_of_pos_right H !nat_of_pnat_pos
 
-theorem half_shrink_strong (n : ℕ+) : (2 * n)⁻¹ < n⁻¹ :=
+theorem inv_two_mul_lt_inv (n : ℕ+) : (2 * n)⁻¹ < n⁻¹ :=
   begin
     rewrite ↑inv,
     apply div_lt_div_of_lt,
     apply rat_of_pnat_is_pos,
     have H : n~ < (2 * n)~, begin
-      rewrite -pnat_one_mul at {1},
+      rewrite -one_mul at {1},
       apply mul_lt_mul_left,
       apply dec_trivial
     end,
@@ -197,24 +195,24 @@ theorem half_shrink_strong (n : ℕ+) : (2 * n)⁻¹ < n⁻¹ :=
     apply H
   end
 
-theorem half_shrink (n : ℕ+) : (2 * n)⁻¹ ≤ n⁻¹ := le_of_lt !half_shrink_strong
+theorem inv_two_mul_le_inv (n : ℕ+) : (2 * n)⁻¹ ≤ n⁻¹ := rat.le_of_lt !inv_two_mul_lt_inv
 
 theorem inv_ge_of_le {p q : ℕ+} (H : p ≤ q) : q⁻¹ ≤ p⁻¹ :=
-  div_le_div_of_le !rat_of_pnat_is_pos (pnat_le_to_rat_le H)
+  div_le_div_of_le !rat_of_pnat_is_pos (rat_of_pnat_le_of_pnat_le H)
 
 theorem inv_gt_of_lt {p q : ℕ+} (H : p < q) : q⁻¹ < p⁻¹ :=
-  div_lt_div_of_lt !rat_of_pnat_is_pos (pnat_lt_to_rat_lt H)
+  div_lt_div_of_lt !rat_of_pnat_is_pos (rat_of_pnat_lt_of_pnat_lt H)
 
 theorem ge_of_inv_le {p q : ℕ+} (H : p⁻¹ ≤ q⁻¹) : q ≤ p :=
-  rat_le_to_pnat_le (le_of_div_le !rat_of_pnat_is_pos H)
+  pnat_le_of_rat_of_pnat_le (le_of_div_le !rat_of_pnat_is_pos H)
 
-theorem two_mul (p : ℕ+) : pnat.to_rat (2 * p) = (1 + 1) * pnat.to_rat p :=
+theorem two_mul (p : ℕ+) : rat_of_pnat (2 * p) = (1 + 1) * rat_of_pnat p :=
   by rewrite pnat_to_rat_mul
 
-theorem padd_halves (p : ℕ+) : (2 * p)⁻¹ + (2 * p)⁻¹ = p⁻¹ :=
+theorem add_halves (p : ℕ+) : (2 * p)⁻¹ + (2 * p)⁻¹ = p⁻¹ :=
   begin
-    rewrite [↑inv, -(@add_halves (1 / (pnat.to_rat p))), *div_div_eq_div_mul'],
-    have H : pnat.to_rat (2 * p) = pnat.to_rat p * (1 + 1), by rewrite [rat.mul.comm, two_mul],
+    rewrite [↑inv, -(@add_halves (1 / (rat_of_pnat p))), *div_div_eq_div_mul'],
+    have H : rat_of_pnat (2 * p) = rat_of_pnat p * (1 + 1), by rewrite [rat.mul.comm, two_mul],
     rewrite *H
   end
 
@@ -222,14 +220,14 @@ theorem add_halves_double (m n : ℕ+) :
         m⁻¹ + n⁻¹ = ((2 * m)⁻¹ + (2 * n)⁻¹) + ((2 * m)⁻¹ + (2 * n)⁻¹) :=
   have simp [visible] : ∀ a b : ℚ, (a + a) + (b + b) = (a + b) + (a + b),
     by intros; rewrite [rat.add.assoc, -(rat.add.assoc a b b), {_+b}rat.add.comm, -*rat.add.assoc],
-  by rewrite [-padd_halves m, -padd_halves n, simp]
+  by rewrite [-add_halves m, -add_halves n, simp]
 
-theorem pnat_div_helper {p q : ℕ+} : (p * q)⁻¹ = p⁻¹ * q⁻¹ :=
+theorem inv_mul_eq_mul_inv {p q : ℕ+} : (p * q)⁻¹ = p⁻¹ * q⁻¹ :=
   by rewrite [↑inv, pnat_to_rat_mul, one_div_mul_one_div''']
 
 theorem inv_mul_le_inv (p q : ℕ+) : (p * q)⁻¹ ≤ q⁻¹ :=
   begin
-    rewrite [pnat_div_helper, -{q⁻¹}rat.one_mul at {2}],
+    rewrite [inv_mul_eq_mul_inv, -{q⁻¹}rat.one_mul at {2}],
     apply rat.mul_le_mul,
     apply inv_le_one,
     apply rat.le.refl,
@@ -239,39 +237,39 @@ theorem inv_mul_le_inv (p q : ℕ+) : (p * q)⁻¹ ≤ q⁻¹ :=
   end
 
 theorem pnat_mul_le_mul_left' (a b c : ℕ+) (H : a ≤ b) : c * a ≤ c * b :=
-  nat.mul_le_mul_of_nonneg_left H (le_of_lt !nat_of_pnat_pos)
+  nat.mul_le_mul_of_nonneg_left H (nat.le_of_lt !nat_of_pnat_pos)
 
-theorem pnat_mul_assoc (a b c : ℕ+) : a * b * c = a * (b * c) :=
+theorem mul.assoc (a b c : ℕ+) : a * b * c = a * (b * c) :=
   pnat.eq !nat.mul.assoc
 
-theorem pnat_mul_comm (a b : ℕ+) : a * b = b * a :=
+theorem mul.comm (a b : ℕ+) : a * b = b * a :=
   pnat.eq !nat.mul.comm
 
-theorem pnat_add_assoc (a b c : ℕ+) : a + b + c = a + (b + c) :=
+theorem add.assoc (a b c : ℕ+) : a + b + c = a + (b + c) :=
   pnat.eq !nat.add.assoc
 
-theorem pnat.mul_le_mul_left (p q : ℕ+) : q ≤ p * q :=
+theorem mul_le_mul_left (p q : ℕ+) : q ≤ p * q :=
   begin
-    rewrite [-pnat_one_mul at {1}, pnat_mul_comm, pnat_mul_comm p],
+    rewrite [-one_mul at {1}, mul.comm, mul.comm p],
     apply pnat_mul_le_mul_left',
     apply pone_le
   end
 
-theorem pnat.mul_le_mul_right (p q : ℕ+) : p ≤ p * q :=
-  by rewrite pnat_mul_comm; apply pnat.mul_le_mul_left
+theorem mul_le_mul_right (p q : ℕ+) : p ≤ p * q :=
+  by rewrite mul.comm; apply mul_le_mul_left
 
 theorem one_lt_two : pone < 2 := dec_trivial
 
 theorem pnat.lt_of_not_le {p q : ℕ+} (H : ¬ p ≤ q) : q < p :=
   nat.lt_of_not_ge H
 
-theorem pnat.inv_cancel (p : ℕ+) : pnat.to_rat p * p⁻¹ = (1 : ℚ) :=
+theorem inv_cancel_left (p : ℕ+) : rat_of_pnat p * p⁻¹ = (1 : ℚ) :=
   mul_one_div_cancel (ne.symm (rat.ne_of_lt !rat_of_pnat_is_pos))
 
-theorem pnat.inv_cancel_right (p : ℕ+) : p⁻¹ * pnat.to_rat p = (1 : ℚ) :=
-  by rewrite rat.mul.comm; apply pnat.inv_cancel
+theorem inv_cancel_right (p : ℕ+) : p⁻¹ * rat_of_pnat p = (1 : ℚ) :=
+  by rewrite rat.mul.comm; apply inv_cancel_left
 
-theorem pnat_lt_add_left (p q : ℕ+) : p < p + q :=
+theorem lt_add_left (p q : ℕ+) : p < p + q :=
   begin
     have H : p~ < p~ + q~, begin
       rewrite -nat.add_zero at {1},
@@ -282,9 +280,9 @@ theorem pnat_lt_add_left (p q : ℕ+) : p < p + q :=
   end
 
 theorem inv_add_lt_left (p q : ℕ+) : (p + q)⁻¹ < p⁻¹ :=
-  by apply inv_gt_of_lt; apply pnat_lt_add_left
+  by apply inv_gt_of_lt; apply lt_add_left
 
-theorem div_le_pnat (q : ℚ) (n : ℕ+) (H : q ≥ n⁻¹) : 1 / q ≤ pnat.to_rat n :=
+theorem div_le_pnat (q : ℚ) (n : ℕ+) (H : q ≥ n⁻¹) : 1 / q ≤ rat_of_pnat n :=
   begin
     apply rat.div_le_of_le_mul,
     apply rat.lt_of_lt_of_le,
@@ -296,10 +294,10 @@ theorem div_le_pnat (q : ℚ) (n : ℕ+) (H : q ≥ n⁻¹) : 1 / q ≤ pnat.to_
     apply H
   end
 
-theorem pnat_cancel' (n m : ℕ+) : (n * n * m)⁻¹ * (pnat.to_rat n * pnat.to_rat n) = m⁻¹ :=
+theorem pnat_cancel' (n m : ℕ+) : (n * n * m)⁻¹ * (rat_of_pnat n * rat_of_pnat n) = m⁻¹ :=
   begin
     have simp : ∀ a b c : ℚ, (a * a * (b * b * c)) = (a * b) * (a * b) * c, from sorry, -- simp
-    rewrite [rat.mul.comm, *pnat_div_helper, simp, *pnat.inv_cancel, *rat.one_mul]
+    rewrite [rat.mul.comm, *inv_mul_eq_mul_inv, simp, *inv_cancel_left, *rat.one_mul]
   end
 
 
diff --git a/library/data/real/basic.lean b/library/data/real/basic.lean
index 69e85234a..f14c392e9 100644
--- a/library/data/real/basic.lean
+++ b/library/data/real/basic.lean
@@ -99,7 +99,7 @@ theorem rewrite_helper7 (a b c d x : ℚ) :
 
 theorem ineq_helper (a b : ℚ) (k m n : ℕ+) (H : a ≤ (k * 2 * m)⁻¹ + (k * 2 * n)⁻¹)
                     (H2 : b ≤ (k * 2 * m)⁻¹ + (k * 2 * n)⁻¹) :
-        (pnat.to_rat k) * a + b * (pnat.to_rat k) ≤ m⁻¹ + n⁻¹ := sorry
+        (rat_of_pnat k) * a + b * (rat_of_pnat k) ≤ m⁻¹ + n⁻¹ := sorry
 
 theorem factor_lemma (a b c d e : ℚ) : abs (a + b + c - (d + (b + e))) = abs ((a - d) + (c - e)) :=
   sorry
@@ -144,7 +144,7 @@ theorem bdd_of_eq {s t : seq} (H : s ≡ t) :
     intros [j, n, Hn],
     apply rat.le.trans,
     apply H n,
-    rewrite -(padd_halves j),
+    rewrite -(add_halves j),
     apply rat.add_le_add,
     apply inv_ge_of_le Hn,
     apply inv_ge_of_le Hn
@@ -206,7 +206,7 @@ theorem pnat_bound {ε : ℚ} (Hε : ε > 0) : ∃ p : ℕ+, p⁻¹ ≤ ε :=
     existsi (pceil (1 / ε)),
     rewrite -(rat.div_div (rat.ne_of_gt Hε)) at {2},
     apply pceil_helper,
-    apply pnat.le.refl
+    apply le.refl
   end
 
 theorem bdd_of_eq_var {s t : seq} (Hs : regular s) (Ht : regular t) (Heq : s ≡ t) :
@@ -235,7 +235,7 @@ theorem equiv.trans (s t u : seq) (Hs : regular s) (Ht : regular t) (Hu : regula
     apply abs_add_le_abs_add_abs,
     have Hst : abs (s n - t n) ≤ (2 * j)⁻¹, from bdd_of_eq H _ _ Hn,
     have Htu : abs (t n - u n) ≤ (2 * j)⁻¹, from bdd_of_eq H2 _ _ Hn,
-    rewrite -(padd_halves j),
+    rewrite -(add_halves j),
     apply rat.add_le_add,
     repeat assumption
   end
@@ -245,7 +245,7 @@ theorem equiv.trans (s t u : seq) (Hs : regular s) (Ht : regular t) (Hu : regula
 
 definition K (s : seq) : ℕ+ := pnat.pos (ubound (abs (s pone)) + 1 + 1) dec_trivial
 
-theorem canon_bound {s : seq} (Hs : regular s) (n : ℕ+) : abs (s n) ≤ pnat.to_rat (K s) :=
+theorem canon_bound {s : seq} (Hs : regular s) (n : ℕ+) : abs (s n) ≤ rat_of_pnat (K s) :=
   calc
     abs (s n) = abs (s n - s pone + s pone) : by rewrite rat.sub_add_cancel
     ... ≤ abs (s n - s pone) + abs (s pone) : abs_add_le_abs_add_abs
@@ -263,7 +263,7 @@ definition K₂ (s t : seq) := max (K s) (K t)
 theorem K₂_symm (s t : seq) : K₂ s t = K₂ t s :=
   if H : K s < K t then
     (have H1 [visible] : K₂ s t = K t, from max_eq_right H,
-      have H2 [visible] : K₂ t s = K t, from max_eq_left (pnat.not_lt_of_le (pnat.le_of_lt H)),
+      have H2 [visible] : K₂ t s = K t, from max_eq_left (not_lt_of_ge (le_of_lt H)),
       by rewrite [H1, -H2])
   else
     (have H1 [visible] : K₂ s t = K s, from max_eq_left H,
@@ -271,20 +271,20 @@ theorem K₂_symm (s t : seq) : K₂ s t = K₂ t s :=
         (have H2 [visible] : K₂ t s = K s, from max_eq_right J, by rewrite [H1, -H2])
       else
         (have Heq [visible] : K t = K s, from
-          pnat.eq_of_le_of_ge (pnat.le_of_not_lt H) (pnat.le_of_not_lt J),
+          eq_of_le_of_ge (le_of_not_gt H) (le_of_not_gt J),
         by rewrite [↑K₂, Heq]))
 
 theorem canon_2_bound_left (s t : seq) (Hs : regular s) (n : ℕ+) :
-        abs (s n) ≤ pnat.to_rat (K₂ s t) :=
+        abs (s n) ≤ rat_of_pnat (K₂ s t) :=
   calc
-    abs (s n) ≤ pnat.to_rat (K s) : canon_bound Hs n
-    ... ≤ pnat.to_rat (K₂ s t) : pnat_le_to_rat_le (!max_left)
+    abs (s n) ≤ rat_of_pnat (K s) : canon_bound Hs n
+    ... ≤ rat_of_pnat (K₂ s t) : rat_of_pnat_le_of_pnat_le (!max_left)
 
 theorem canon_2_bound_right (s t : seq) (Ht : regular t) (n : ℕ+) :
-        abs (t n) ≤ pnat.to_rat (K₂ s t) :=
+        abs (t n) ≤ rat_of_pnat (K₂ s t) :=
   calc
-    abs (t n) ≤ pnat.to_rat (K t) : canon_bound Ht n
-    ... ≤ pnat.to_rat (K₂ s t) : pnat_le_to_rat_le (!max_right)
+    abs (t n) ≤ rat_of_pnat (K t) : canon_bound Ht n
+    ... ≤ rat_of_pnat (K₂ s t) : rat_of_pnat_le_of_pnat_le (!max_right)
 
 definition sadd (s t : seq) : seq := λ n, (s (2 * n)) + (t (2 * n))
 
@@ -361,8 +361,8 @@ theorem s_add_assoc (s t u : seq) (Hs : regular s) (Hu : regular u) :
     apply rat.le.trans,
     rotate 1,
     apply rat.add_le_add_right,
-    apply half_shrink,
-    rewrite [-(padd_halves (2 * n)), -(padd_halves n), factor_lemma_2],
+    apply inv_two_mul_le_inv,
+    rewrite [-(add_halves (2 * n)), -(add_halves n), factor_lemma_2],
     apply rat.add_le_add,
     apply Hs,
     apply Hu
@@ -406,7 +406,7 @@ theorem s_mul_assoc_lemma (s t u : seq) (a b c d : ℕ+) :
     apply abs_nonneg
   end
 
-definition Kq (s : seq) := pnat.to_rat (K s) + 1
+definition Kq (s : seq) := rat_of_pnat (K s) + 1
 theorem Kq_bound {s : seq} (H : regular s) : ∀ n, abs (s n) ≤ Kq s :=
   begin
     intros,
@@ -421,7 +421,7 @@ theorem Kq_bound_nonneg {s : seq} (H : regular s) : 0 ≤ Kq s :=
   rat.le.trans !abs_nonneg (Kq_bound H 2)
 
 theorem Kq_bound_pos {s : seq} (H : regular s) : 0 < Kq s :=
-  have H1 : 0 ≤ pnat.to_rat (K s), from rat.le.trans (!abs_nonneg) (canon_bound H 2),
+  have H1 : 0 ≤ rat_of_pnat (K s), from rat.le.trans (!abs_nonneg) (canon_bound H 2),
   add_pos_of_nonneg_of_pos H1 rat.zero_lt_one
 
 theorem s_mul_assoc_lemma_5 {s t u : seq} (Hs : regular s) (Ht : regular t) (Hu : regular u)
@@ -492,7 +492,7 @@ theorem s_mul_assoc {s t u : seq} (Hs : regular s) (Ht : regular t) (Hu : regula
     fapply exists.intro,
     rotate 1,
     intros,
-    rewrite [↑smul, *DK_rewrite, *TK_rewrite, -*pnat_mul_assoc, -*rat.mul.assoc],
+    rewrite [↑smul, *DK_rewrite, *TK_rewrite, -*pnat.mul.assoc, -*rat.mul.assoc],
     apply rat.le.trans,
     apply s_mul_assoc_lemma,
     apply rat.le.trans,
@@ -538,7 +538,7 @@ theorem s_zero_add (s : seq) (H : regular s) : sadd zero s ≡ s :=
     apply rat.le.trans,
     apply H,
     apply rat.add_le_add,
-    apply half_shrink,
+    apply inv_two_mul_le_inv,
     apply rat.le.refl
   end
 
@@ -550,7 +550,7 @@ theorem s_add_zero (s : seq) (H : regular s) : sadd s zero ≡ s :=
     apply rat.le.trans,
     apply H,
     apply rat.add_le_add,
-    apply half_shrink,
+    apply inv_two_mul_le_inv,
     apply rat.le.refl
   end
 
@@ -594,16 +594,16 @@ theorem add_well_defined {s t u v : seq} (Hs : regular s) (Ht : regular t) (Hu :
 theorem mul_bound_helper {s t : seq} (Hs : regular s) (Ht : regular t) (a b c : ℕ+) (j : ℕ+) :
         ∃ N : ℕ+, ∀ n : ℕ+, n ≥ N → abs (s (a * n) * t (b * n) - s (c * n) * t (c * n)) ≤ j⁻¹ :=
   begin
-    existsi pceil (((pnat.to_rat (K s)) * (b⁻¹ + c⁻¹) + (a⁻¹ + c⁻¹) *
-                   (pnat.to_rat (K t))) * (pnat.to_rat j)),
+    existsi pceil (((rat_of_pnat (K s)) * (b⁻¹ + c⁻¹) + (a⁻¹ + c⁻¹) *
+                   (rat_of_pnat (K t))) * (rat_of_pnat j)),
     intros n Hn,
     rewrite rewrite_helper4,
     apply rat.le.trans,
     apply abs_add_le_abs_add_abs,
     apply rat.le.trans,
     rotate 1,
-    show n⁻¹ * ((pnat.to_rat (K s)) * (b⁻¹ + c⁻¹)) +
-         n⁻¹ * ((a⁻¹ + c⁻¹) * (pnat.to_rat (K t))) ≤ j⁻¹, begin
+    show n⁻¹ * ((rat_of_pnat (K s)) * (b⁻¹ + c⁻¹)) +
+         n⁻¹ * ((a⁻¹ + c⁻¹) * (rat_of_pnat (K t))) ≤ j⁻¹, begin
         rewrite -rat.left_distrib,
         apply rat.le.trans,
         apply rat.mul_le_mul_of_nonneg_right,
@@ -631,7 +631,7 @@ theorem mul_bound_helper {s t : seq} (Hs : regular s) (Ht : regular t) (a b c :
     apply abs_nonneg,
     apply rat.le_of_lt,
     apply rat_of_pnat_is_pos,
-    rewrite [*pnat_div_helper, -rat.right_distrib, -rat.mul.assoc, rat.mul.comm],
+    rewrite [*inv_mul_eq_mul_inv, -rat.right_distrib, -rat.mul.assoc, rat.mul.comm],
     apply rat.mul_le_mul_of_nonneg_left,
     apply rat.le.refl,
     apply rat.le_of_lt,
@@ -644,7 +644,7 @@ theorem mul_bound_helper {s t : seq} (Hs : regular s) (Ht : regular t) (a b c :
     apply Ht,
     apply abs_nonneg,
     apply add_invs_nonneg,
-    rewrite [*pnat_div_helper, -rat.right_distrib, mul.comm _ n⁻¹, rat.mul.assoc],
+    rewrite [*inv_mul_eq_mul_inv, -rat.right_distrib, mul.comm _ n⁻¹, rat.mul.assoc],
     apply rat.mul_le_mul,
     apply rat.le.refl,
     apply rat.le.refl,
@@ -661,16 +661,7 @@ theorem s_distrib {s t u : seq} (Hs : regular s) (Ht : regular t) (Hu : regular
                   smul s (sadd t u) ≡ sadd (smul s t) (smul s u) :=
   begin
     apply eq_of_bdd,
-    apply reg_mul_reg,
-    assumption,
-    apply reg_add_reg,
-    repeat assumption,
-    apply reg_add_reg,
-    repeat assumption,
-    apply reg_mul_reg,
-    repeat assumption,
-    apply reg_mul_reg,
-    repeat assumption,
+    repeat (assumption | apply reg_add_reg | apply reg_mul_reg),
     intros,
     let exh1 := λ a b c, mul_bound_helper Hs Ht a b c (2 * j),
     apply exists.elim,
@@ -684,16 +675,16 @@ theorem s_distrib {s t u : seq} (Hs : regular s) (Ht : regular t) (Hu : regular
     intros N2 HN2,
     existsi max N1 N2,
     intros n Hn,
-    rewrite [↑sadd at *, ↑smul, rewrite_helper3, -padd_halves j, -*pnat_mul_assoc at *],
+    rewrite [↑sadd at *, ↑smul, rewrite_helper3, -add_halves j, -*pnat.mul.assoc at *],
     apply rat.le.trans,
     apply abs_add_le_abs_add_abs,
     apply rat.add_le_add,
     apply HN1,
-    apply ple.trans,
+    apply le.trans,
     apply max_left N1 N2,
     apply Hn,
     apply HN2,
-    apply ple.trans,
+    apply le.trans,
     apply max_right N1 N2,
     apply Hn
   end
@@ -717,7 +708,7 @@ theorem mul_zero_equiv_zero {s t : seq} (Hs : regular s) (Ht : regular t) (Htz :
     apply Kq_bound Hs,
     let HN' := λ n, (!rat.sub_zero ▸ HN n),
     apply HN',
-    apply ple.trans Hn,
+    apply le.trans Hn,
     apply pnat.mul_le_mul_left,
     apply abs_nonneg,
     apply rat.le_of_lt (Kq_bound_pos Hs),
@@ -761,10 +752,10 @@ theorem equiv_of_diff_equiv_zero {s t : seq} (Hs : regular s) (Ht : regular t)
     let He' := λ a b c, !rat.sub_zero ▸ (He a b c),
     apply (He' _ _ Hn),
     apply Ht,
-    rewrite [simp, padd_halves, -(padd_halves j), -(padd_halves (2 * j)), -*rat.add.assoc],
+    rewrite [simp, add_halves, -(add_halves j), -(add_halves (2 * j)), -*rat.add.assoc],
     apply rat.add_le_add_right,
     apply add_le_add_three,
-    repeat (apply rat.le.trans; apply inv_ge_of_le Hn; apply half_shrink)
+    repeat (apply rat.le.trans; apply inv_ge_of_le Hn; apply inv_two_mul_le_inv)
   end
 
 theorem s_sub_cancel (s : seq) : sadd s (sneg s) ≡ zero :=
@@ -913,13 +904,13 @@ theorem zero_nequiv_one : ¬ zero ≡ one :=
     intro Hz,
     rewrite [↑equiv at Hz, ↑zero at Hz, ↑one at Hz],
     let H := Hz (2 * 2),
-    rewrite [rat.zero_sub at H, abs_neg at H, padd_halves at H],
+    rewrite [rat.zero_sub at H, abs_neg at H, add_halves at H],
     have H' : pone⁻¹ ≤ 2⁻¹, from calc
       pone⁻¹ = 1 : by rewrite -pone_inv
       ... = abs 1 : abs_of_pos zero_lt_one
       ... ≤ 2⁻¹ : H,
     let H'' := ge_of_inv_le H',
-    apply absurd (one_lt_two) (pnat.not_lt_of_le H'')
+    apply absurd (one_lt_two) (not_lt_of_ge H'')
   end
 
 ---------------------------------------------
diff --git a/library/data/real/complete.lean b/library/data/real/complete.lean
index 62275df34..132032f03 100644
--- a/library/data/real/complete.lean
+++ b/library/data/real/complete.lean
@@ -11,13 +11,14 @@ At this point, we no longer proceed constructively: this file makes heavy use of
 Here, we show that ℝ is complete.
 -/
 
-import data.real.basic data.real.order data.real.division data.rat data.nat logic.axioms.classical
+import data.real.basic data.real.order data.real.division data.rat data.nat data.pnat logic.axioms.classical
 open -[coercions] rat
 local notation 0 := rat.of_num 0
 local notation 1 := rat.of_num 1
 open -[coercions] nat
 open algebra
 open eq.ops
+open pnat
 
 
 local notation 2 := pnat.pos (nat.of_num 2) dec_trivial
@@ -47,7 +48,7 @@ theorem rat_approx_l1 {s : seq} (H : regular s) :
     intro m Hm,
     apply rat.le.trans,
     apply H,
-    rewrite -(padd_halves n),
+    rewrite -(add_halves n),
     apply rat.add_le_add_right,
     apply inv_ge_of_le Hm
   end
@@ -73,9 +74,9 @@ theorem rat_approx {s : seq} (H : regular s) :
     rotate 1,
     apply rat.sub_le_sub_left,
     apply HN,
-    apply ple.trans,
+    apply pnat.le.trans,
     apply Hp,
-    rewrite -*pnat_mul_assoc,
+    rewrite -*pnat.mul.assoc,
     apply pnat.mul_le_mul_left,
     rewrite [sub_self, -neg_zero],
     apply neg_le_neg,
@@ -112,7 +113,7 @@ theorem const_bound {s : seq} (Hs : regular s) (n : ℕ+) : s_le (s_abs (sadd s
     apply rat.le.trans,
     apply Hs,
     apply rat.add_le_add_right,
-    rewrite -*pnat_mul_assoc,
+    rewrite -*pnat.mul.assoc,
     apply inv_ge_of_le,
     apply pnat.mul_le_mul_left
   end
@@ -185,7 +186,7 @@ theorem equiv_abs_of_ge_zero {s : seq} (Hs : regular s) (Hz : s_le zero s) : s_a
     apply rat.le.trans,
     apply rat.add_le_add,
     repeat (apply inv_ge_of_le; apply Hn),
-    rewrite padd_halves,
+    rewrite pnat.add_halves,
     apply rat.le.refl
   end
 
@@ -217,7 +218,7 @@ theorem equiv_neg_abs_of_le_zero {s : seq} (Hs : regular s) (Hz : s_le s zero) :
     apply rat.le.trans,
     apply rat.add_le_add,
     repeat (apply inv_ge_of_le; apply Hn),
-    rewrite padd_halves,
+    rewrite pnat.add_halves,
     apply rat.le.refl,
     intro Hneg,
     let Hneg' := lt_of_not_ge Hneg,
@@ -253,7 +254,7 @@ theorem add_consts (a b : ℚ) : const a + const b = const (a + b) :=
 theorem sub_consts (a b : ℚ) : const a - const b = const (a - b) := !add_consts
 
 theorem add_half_const (n : ℕ+) : const (2 * n)⁻¹ + const (2 * n)⁻¹ = const (n⁻¹) :=
-  by rewrite [add_consts, padd_halves]
+  by rewrite [add_consts, pnat.add_halves]
 
 theorem const_le_const_of_le (a b : ℚ) : a ≤ b → const a ≤ const b :=
   s.r_const_le_const_of_le
@@ -353,10 +354,10 @@ theorem lim_seq_reg_helper {X : r_seq} {M : ℕ+ → ℕ+} (Hc : cauchy X M) {m
     rotate 1,
     apply Nb_spec_right,
     rotate 1,
-    apply ple.trans,
+    apply pnat.le.trans,
     apply Hmn,
     apply Nb_spec_right,
-    rewrite [*add_consts, rat.add.assoc, padd_halves],
+    rewrite [*add_consts, rat.add.assoc, pnat.add_halves],
     apply const_le_const_of_le,
     apply rat.add_le_add_right,
     apply inv_ge_of_le,
@@ -421,18 +422,18 @@ theorem converges_of_cauchy {X : r_seq} {M : ℕ+ → ℕ+} (Hc : cauchy X M) :
     apply algebra.le.trans,
     apply algebra.add_le_add_three,
     apply Hc,
-    apply ple.trans,
+    apply pnat.le.trans,
     rotate 1,
     apply Hn,
     rotate_right 1,
     apply Nb_spec_right,
     have HMk : M (2 * k) ≤ Nb M n, begin
-      apply ple.trans,
+      apply pnat.le.trans,
       apply Nb_spec_right,
-      apply ple.trans,
+      apply pnat.le.trans,
       apply Hn,
-      apply ple.trans,
-      apply pnat.mul_le_mul_left 3,
+      apply pnat.le.trans,
+      apply mul_le_mul_left 3,
       apply Nb_spec_left
     end,
     apply HMk,
@@ -446,18 +447,18 @@ theorem converges_of_cauchy {X : r_seq} {M : ℕ+ → ℕ+} (Hc : cauchy X M) :
     apply rat.le.refl,
     apply inv_ge_of_le,
     apply pnat_mul_le_mul_left',
-    apply ple.trans,
+    apply pnat.le.trans,
     rotate 1,
     apply Hn,
     rotate_right 1,
     apply Nb_spec_left,
     apply inv_ge_of_le,
-    apply ple.trans,
+    apply pnat.le.trans,
     rotate 1,
     apply Hn,
     rotate_right 1,
     apply Nb_spec_left,
-    rewrite [-*pnat_mul_assoc, p_add_fractions],
+    rewrite [-*pnat.mul.assoc, p_add_fractions],
     apply rat.le.refl
   end
 
diff --git a/library/data/real/division.lean b/library/data/real/division.lean
index 9c709bd49..91c384a06 100644
--- a/library/data/real/division.lean
+++ b/library/data/real/division.lean
@@ -157,7 +157,7 @@ theorem s_inv_of_sep_gt_p {s : seq} (Hs : regular s) (Hsep : sep s zero) {n : 
   begin
     apply eq.trans,
     apply dif_pos Hsep,
-    apply dif_neg (pnat.not_lt_of_le Hn)
+    apply dif_neg (pnat.not_lt_of_ge Hn)
   end
 
 theorem s_inv_of_pos_lt_p {s : seq} (Hs : regular s) (Hpos : pos s) {n : ℕ+}
@@ -170,7 +170,7 @@ theorem s_inv_of_pos_gt_p {s : seq} (Hs : regular s) (Hpos : pos s) {n : ℕ+}
   s_inv_of_sep_gt_p Hs (sep_zero_of_pos Hs Hpos) Hn
 
 theorem le_ps {s : seq} (Hs : regular s) (Hsep : sep s zero) (n : ℕ+) :
-        abs (s_inv Hs n) ≤ (pnat.to_rat (ps Hs Hsep)) :=
+        abs (s_inv Hs n) ≤ (rat_of_pnat (ps Hs Hsep)) :=
   if Hn : n < ps Hs Hsep then
     (begin
       rewrite [(s_inv_of_sep_lt_p Hs Hsep Hn), abs_one_div],
@@ -183,7 +183,7 @@ theorem le_ps {s : seq} (Hs : regular s) (Hsep : sep s zero) (n : ℕ+) :
       rewrite [(s_inv_of_sep_gt_p Hs Hsep (le_of_not_gt Hn)), abs_one_div],
       apply div_le_pnat,
       apply ps_spec,
-      rewrite pnat_mul_assoc,
+      rewrite pnat.mul.assoc,
       apply pnat.mul_le_mul_right
     end)
 
@@ -217,13 +217,13 @@ theorem reg_inv_reg {s : seq} (Hs : regular s) (Hsep : sep s zero) : regular (s_
     rewrite ↑regular,
     intros,
     have Hsp : s ((ps Hs Hsep) * (ps Hs Hsep) * (ps Hs Hsep)) ≠ 0, from
-      s_ne_zero_of_ge_p Hs Hsep !pnat.mul_le_mul_left,
+      s_ne_zero_of_ge_p Hs Hsep !mul_le_mul_left,
     have Hspn : s ((ps Hs Hsep) * (ps Hs Hsep) * n) ≠ 0, from
       s_ne_zero_of_ge_p Hs Hsep (show (ps Hs Hsep) * (ps Hs Hsep) * n ≥ ps Hs Hsep, by
-        rewrite pnat_mul_assoc; apply pnat.mul_le_mul_right),
+        rewrite pnat.mul.assoc; apply pnat.mul_le_mul_right),
     have Hspm : s ((ps Hs Hsep) * (ps Hs Hsep) * m) ≠ 0, from
       s_ne_zero_of_ge_p Hs Hsep (show (ps Hs Hsep) * (ps Hs Hsep) * m ≥ ps Hs Hsep, by
-        rewrite pnat_mul_assoc; apply pnat.mul_le_mul_right),
+        rewrite pnat.mul.assoc; apply pnat.mul_le_mul_right),
     apply @decidable.cases_on (m < (ps Hs Hsep)) _ _,
       intro Hmlt,
       apply @decidable.cases_on (n < (ps Hs Hsep)) _ _,
@@ -233,7 +233,7 @@ theorem reg_inv_reg {s : seq} (Hs : regular s) (Hsep : sep s zero) : regular (s_
         apply add_invs_nonneg,
        intro Hnlt,
        rewrite [(s_inv_of_sep_lt_p Hs Hsep Hmlt),
-                (s_inv_of_sep_gt_p Hs Hsep (pnat.le_of_not_lt Hnlt))],
+                (s_inv_of_sep_gt_p Hs Hsep (le_of_not_gt Hnlt))],
        rewrite [(div_sub_div Hsp Hspn), div_eq_mul_one_div, *abs_mul, *mul_one, *one_mul],
        apply rat.le.trans,
        apply rat.mul_le_mul,
@@ -242,7 +242,7 @@ theorem reg_inv_reg {s : seq} (Hs : regular s) (Hsep : sep s zero) : regular (s_
        apply rat.mul_le_mul,
        rewrite -(s_inv_of_sep_lt_p Hs Hsep Hmlt),
        apply le_ps Hs Hsep,
-       rewrite  -(s_inv_of_sep_gt_p Hs Hsep (pnat.le_of_not_lt Hnlt)),
+       rewrite  -(s_inv_of_sep_gt_p Hs Hsep (le_of_not_gt Hnlt)),
        apply le_ps Hs Hsep,
        apply abs_nonneg,
        apply le_of_lt !rat_of_pnat_is_pos,
@@ -257,14 +257,14 @@ theorem reg_inv_reg {s : seq} (Hs : regular s) (Hsep : sep s zero) : regular (s_
       apply @decidable.cases_on (n < (ps Hs Hsep)) _ _,
         intro Hnlt,
         rewrite [(s_inv_of_sep_lt_p Hs Hsep Hnlt),
-                 (s_inv_of_sep_gt_p Hs Hsep (pnat.le_of_not_lt Hmlt))],
+                 (s_inv_of_sep_gt_p Hs Hsep (le_of_not_gt Hmlt))],
         rewrite [(div_sub_div Hspm Hsp), div_eq_mul_one_div, *abs_mul, *mul_one, *one_mul],
         apply rat.le.trans,
         apply rat.mul_le_mul,
         apply Hs,
         xrewrite [-(mul_one 1), -(div_mul_div Hspm Hsp), abs_mul],
         apply rat.mul_le_mul,
-        rewrite -(s_inv_of_sep_gt_p Hs Hsep (pnat.le_of_not_lt Hmlt)),
+        rewrite -(s_inv_of_sep_gt_p Hs Hsep (le_of_not_gt Hmlt)),
         apply le_ps Hs Hsep,
         rewrite -(s_inv_of_sep_lt_p Hs Hsep Hnlt),
         apply le_ps Hs Hsep,
@@ -278,17 +278,17 @@ theorem reg_inv_reg {s : seq} (Hs : regular s) (Hsep : sep s zero) : regular (s_
         apply pnat.le_of_lt,
         apply Hnlt,
       intro Hnlt,
-      rewrite [(s_inv_of_sep_gt_p Hs Hsep (pnat.le_of_not_lt Hnlt)),
-              (s_inv_of_sep_gt_p Hs Hsep (pnat.le_of_not_lt Hmlt))],
+      rewrite [(s_inv_of_sep_gt_p Hs Hsep (le_of_not_gt Hnlt)),
+              (s_inv_of_sep_gt_p Hs Hsep (le_of_not_gt Hmlt))],
       rewrite [(div_sub_div Hspm Hspn), div_eq_mul_one_div, abs_mul, *one_mul, *mul_one],
       apply rat.le.trans,
       apply rat.mul_le_mul,
       apply Hs,
       xrewrite [-(mul_one 1), -(div_mul_div Hspm Hspn), abs_mul],
       apply rat.mul_le_mul,
-      rewrite -(s_inv_of_sep_gt_p Hs Hsep (pnat.le_of_not_lt Hmlt)),
+      rewrite -(s_inv_of_sep_gt_p Hs Hsep (le_of_not_gt Hmlt)),
       apply le_ps Hs Hsep,
-      rewrite -(s_inv_of_sep_gt_p Hs Hsep (pnat.le_of_not_lt Hnlt)),
+      rewrite -(s_inv_of_sep_gt_p Hs Hsep (le_of_not_gt Hnlt)),
       apply le_ps Hs Hsep,
       apply abs_nonneg,
       apply le_of_lt !rat_of_pnat_is_pos,
@@ -304,7 +304,7 @@ theorem s_inv_ne_zero {s : seq} (Hs : regular s) (Hsep : sep s zero) (n : ℕ+)
       rewrite (s_inv_of_sep_gt_p Hs Hsep H),
       apply one_div_ne_zero,
       apply s_ne_zero_of_ge_p,
-      apply ple.trans,
+      apply pnat.le.trans,
       apply H,
       apply pnat.mul_le_mul_left
     end)
@@ -333,40 +333,40 @@ theorem mul_inv {s : seq} (Hs : regular s) (Hsep : sep s zero) : smul s (s_inv H
     apply Rsi,
     apply abs_nonneg,
     have Hp : (K₂ s (s_inv Hs)) * 2 * n ≥ ps Hs Hsep, begin
-      apply ple.trans,
+      apply pnat.le.trans,
       apply max_left,
       rotate 1,
-      apply ple.trans,
+      apply pnat.le.trans,
       apply Hn,
       apply pnat.mul_le_mul_left
     end,
     have Hnz' : s (((ps Hs Hsep) * (ps Hs Hsep)) * ((K₂ s (s_inv Hs)) * 2 * n)) ≠ 0, from
       s_ne_zero_of_ge_p Hs Hsep
         (show ps Hs Hsep ≤ ((ps Hs Hsep) * (ps Hs Hsep)) * ((K₂ s (s_inv Hs)) * 2 * n),
-          by rewrite *pnat_mul_assoc; apply pnat.mul_le_mul_right),
+          by rewrite *pnat.mul.assoc; apply pnat.mul_le_mul_right),
     xrewrite [(s_inv_of_sep_gt_p Hs Hsep Hp), (div_div Hnz')],
     apply rat.le.trans,
     apply rat.mul_le_mul_of_nonneg_left,
     apply Hs,
     apply le_of_lt,
     apply rat_of_pnat_is_pos,
-    xrewrite [rat.mul.left_distrib, pnat_mul_comm ((ps Hs Hsep) * (ps Hs Hsep)), *pnat_mul_assoc,
-            *(@pnat_div_helper (K₂ s (s_inv Hs))), -*rat.mul.assoc, *pnat.inv_cancel,
-            *one_mul, -(padd_halves j)],
+    xrewrite [rat.mul.left_distrib, mul.comm ((ps Hs Hsep) * (ps Hs Hsep)), *pnat.mul.assoc,
+            *(@inv_mul_eq_mul_inv (K₂ s (s_inv Hs))), -*rat.mul.assoc, *inv_cancel_left,
+            *one_mul, -(add_halves j)],
     apply rat.add_le_add,
     apply inv_ge_of_le,
     apply pnat_mul_le_mul_left',
-    apply ple.trans,
+    apply pnat.le.trans,
     rotate 1,
     apply Hn,
     rotate_right 1,
     apply max_right,
     apply inv_ge_of_le,
     apply pnat_mul_le_mul_left',
-    apply ple.trans,
+    apply pnat.le.trans,
     apply max_right,
     rotate 1,
-    apply ple.trans,
+    apply pnat.le.trans,
     apply Hn,
     apply pnat.mul_le_mul_right
    end
diff --git a/library/data/real/order.lean b/library/data/real/order.lean
index 5b5184858..1d5300870 100644
--- a/library/data/real/order.lean
+++ b/library/data/real/order.lean
@@ -82,7 +82,7 @@ theorem pos_of_bdd_away {s : seq} (H : ∃ N : ℕ+, ∀ n : ℕ+, n ≥ N → (
     apply inv_add_lt_left,
     apply HN,
     apply pnat.le_of_lt,
-    apply pnat_lt_add_left
+    apply lt_add_left
   end
 
 theorem bdd_within_of_nonneg {s : seq} (Hs : regular s) (H : nonneg s) :
@@ -149,13 +149,13 @@ theorem pos_of_pos_equiv {s t : seq} (Hs : regular s) (Heq : s ≡ t) (Hp : pos
     rotate 1,
     apply ge_sub_of_abs_sub_le_right,
     apply Heq,
-    have Hs4 : N⁻¹ ≤ s (2 * 2 * N), from HN _ (!pnat.mul_le_mul_left),
+    have Hs4 : N⁻¹ ≤ s (2 * 2 * N), from HN _ (!mul_le_mul_left),
     apply lt_of_lt_of_le,
     rotate 1,
     apply iff.mp' (rat.add_le_add_right_iff _ _ _),
     apply Hs4,
-    rewrite [*pnat_mul_assoc, padd_halves, -(padd_halves N), rat.add_sub_cancel],
-    apply half_shrink_strong
+    rewrite [*pnat.mul.assoc, pnat.add_halves, -(add_halves N), rat.add_sub_cancel],
+    apply inv_two_mul_lt_inv
   end
 
 
@@ -178,14 +178,14 @@ theorem nonneg_of_nonneg_equiv {s t : seq} (Hs : regular s) (Ht : regular t) (He
     rotate 1,
     apply rat.sub_le_sub_right,
     apply HNs,
-    apply ple.trans,
+    apply pnat.le.trans,
     rotate 1,
     apply Hm,
     rotate_right 1,
     apply max_left,
     have Hms : m⁻¹ ≤ (2 * 2 * n)⁻¹, begin
          apply inv_ge_of_le,
-         apply ple.trans,
+         apply pnat.le.trans,
          rotate 1,
          apply Hm;
          apply max_right
@@ -195,10 +195,10 @@ theorem nonneg_of_nonneg_equiv {s t : seq} (Hs : regular s) (Ht : regular t) (He
     rotate 1,
     apply rat.sub_le_sub_left,
     apply Hms',
-    rewrite [*pnat_mul_assoc, padd_halves, -neg_add, -padd_halves n],
+    rewrite [*pnat.mul.assoc, pnat.add_halves, -neg_add, -add_halves n],
     apply neg_le_neg,
     apply rat.add_le_add_right,
-    apply half_shrink
+    apply inv_two_mul_le_inv
   end
 
 definition s_le (a b : seq) := nonneg (sadd b (sneg a))
@@ -336,7 +336,7 @@ theorem add_nonneg_of_nonneg {s t : seq} (Hs : nonneg s) (Ht : nonneg t) : nonne
   begin
     rewrite [↑nonneg at *, ↑sadd],
     intros,
-    rewrite [-padd_halves, neg_add],
+    rewrite [-pnat.add_halves, neg_add],
     apply add_le_add,
     apply Hs,
     apply Ht
@@ -530,27 +530,27 @@ theorem s_mul_pos_of_pos {s t : seq} (Hs : regular s) (Ht : regular t) (Hps : po
     rotate 1,
     apply rat.mul_le_mul,
     apply HNs,
-    apply ple.trans,
+    apply pnat.le.trans,
     apply max_left Ns Nt,
-    rewrite -pnat_mul_assoc,
+    rewrite -pnat.mul.assoc,
     apply pnat.mul_le_mul_left,
     apply HNt,
-    apply ple.trans,
+    apply pnat.le.trans,
     apply max_right Ns Nt,
-    rewrite -pnat_mul_assoc,
+    rewrite -pnat.mul.assoc,
     apply pnat.mul_le_mul_left,
     apply le_of_lt,
     apply inv_pos,
     apply rat.le.trans,
     rotate 1,
     apply HNs,
-    apply ple.trans,
+    apply pnat.le.trans,
     apply max_left Ns Nt,
-    rewrite -pnat_mul_assoc,
+    rewrite -pnat.mul.assoc,
     apply pnat.mul_le_mul_left,
-    rewrite pnat_div_helper,
+    rewrite inv_mul_eq_mul_inv,
     apply rat.mul_lt_mul,
-    rewrite [pnat_div_helper, -one_mul Ns⁻¹],
+    rewrite [inv_mul_eq_mul_inv, -one_mul Ns⁻¹],
     apply rat.mul_lt_mul,
     apply inv_lt_one_of_gt,
     apply dec_trivial,
@@ -652,7 +652,7 @@ theorem s_mul_nonneg_of_nonneg {s t : seq} (Hs : regular s) (Ht : regular t)
       rotate 1,
       rewrite -neg_mul_eq_mul_neg,
       apply neg_le_neg,
-      rewrite [*pnat_mul_assoc, pnat_div_helper, -mul.assoc, pnat.inv_cancel, one_mul],
+      rewrite [*pnat.mul.assoc, inv_mul_eq_mul_inv, -mul.assoc, inv_cancel_left, one_mul],
       apply inv_ge_of_le,
       apply pnat.mul_le_mul_left,
      intro Hsn,
@@ -675,7 +675,7 @@ theorem s_mul_nonneg_of_nonneg {s t : seq} (Hs : regular s) (Ht : regular t)
      rotate 1,
      rewrite -neg_mul_eq_neg_mul,
      apply neg_le_neg,
-     rewrite [*pnat_mul_assoc, pnat_div_helper, mul.comm, -mul.assoc, pnat.inv_cancel, one_mul],
+     rewrite [*pnat.mul.assoc, inv_mul_eq_mul_inv, mul.comm, -mul.assoc, inv_cancel_left, one_mul],
      apply inv_ge_of_le,
      apply pnat.mul_le_mul_left,
     intro Htn,
@@ -832,20 +832,20 @@ theorem s_lt_of_lt_of_le {s t u : seq} (Hs : regular s) (Ht : regular t) (Hu : r
     rotate 1,
     apply rat.add_le_add,
     apply HNt,
-    apply ple.trans,
-    apply pnat.mul_le_mul_left 2,
-    apply ple.trans,
+    apply pnat.le.trans,
+    apply mul_le_mul_left 2,
+    apply pnat.le.trans,
     rotate 1,
     apply Hn,
     rotate_right 1,
     apply max_left,
     apply HNu,
-    apply ple.trans,
+    apply pnat.le.trans,
     rotate 1,
     apply Hn,
     rotate_right 1,
     apply max_right,
-    rewrite [-padd_halves Nt, rat.add_sub_cancel],
+    rewrite [-add_halves Nt, rat.add_sub_cancel],
     apply inv_ge_of_le,
     apply max_left
   end
@@ -872,20 +872,20 @@ theorem s_lt_of_le_of_lt {s t u : seq} (Hs : regular s) (Ht : regular t) (Hu : r
     rotate 1,
     apply rat.add_le_add,
     apply HNt,
-    apply ple.trans,
+    apply pnat.le.trans,
     rotate 1,
     apply Hn,
     rotate_right 1,
     apply max_right,
     apply HNu,
-    apply ple.trans,
-    apply pnat.mul_le_mul_left 2,
-    apply ple.trans,
+    apply pnat.le.trans,
+    apply mul_le_mul_left 2,
+    apply pnat.le.trans,
     rotate 1,
     apply Hn,
     rotate_right 1,
     apply max_left,
-    rewrite [-padd_halves Nu, neg_add_cancel_left],
+    rewrite [-add_halves Nu, neg_add_cancel_left],
     apply inv_ge_of_le,
     apply max_left
   end