diff --git a/piclib/built-in.scm b/piclib/built-in.scm
index da9f3974..0a2fbca0 100644
--- a/piclib/built-in.scm
+++ b/piclib/built-in.scm
@@ -316,24 +316,6 @@
 	pivot
 	(loop (if (> x (car rest)) x (car rest)) (cdr rest)))))
 
-;;; so ugly code, must rewrite everything as soon as possible...
-(define-macro (define-transitive-predicate op)
-  `(define (,op . args)
-     (call/cc
-      (lambda (exit)
-	(do ((val (car args))
-	     (nums (cdr args) (cdr nums)))
-	    ((pair? nums) #t)
-	  (if (,op val (car nums))
-	      (set! val (car nums))
-	      (exit #f)))))))
-
-(define-transitive-predicate =)
-(define-transitive-predicate <)
-(define-transitive-predicate >)
-(define-transitive-predicate <=)
-(define-transitive-predicate >=)
-
 (define (floor/ n m)
   (values (floor-quotient n m)
 	  (floor-remainder n m)))
diff --git a/src/number.c b/src/number.c
index f2e1b3e5..841372cf 100644
--- a/src/number.c
+++ b/src/number.c
@@ -79,6 +79,40 @@ pic_number_nan_p(pic_state *pic)
     return pic_false_value();
 }
 
+#define DEFINE_MATH_PRED(op, name)			\
+  static pic_value					\
+  pic_number_##name(pic_state *pic)			\
+  {							\
+    int argc, i;					\
+    pic_value *argv;					\
+    double f,g;						\
+    							\
+    pic_get_args(pic, "ff*", &f, &g, &argc, &argv);	\
+    							\
+    if (! (f op g))					\
+      return pic_false_value();				\
+    							\
+    for (i = 0; i < argc; ++i) {			\
+      if (pic_float_p(argv[i]))				\
+	g = pic_float(argv[i]);				\
+      else if (pic_int_p(argv[i]))			\
+	g = pic_int(argv[i]);				\
+      else						\
+	pic_error(pic, #op ": number required");	\
+      							\
+      if (! (f op g))					\
+	return pic_false_value();			\
+    }							\
+    							\
+    return pic_true_value();				\
+  }
+
+DEFINE_MATH_PRED(=, eq)
+DEFINE_MATH_PRED(<, lt)
+DEFINE_MATH_PRED(>, gt)
+DEFINE_MATH_PRED(<=, le)
+DEFINE_MATH_PRED(>=, ge)
+
 static pic_value
 pic_number_abs(pic_state *pic)
 {
@@ -399,6 +433,11 @@ pic_init_number(pic_state *pic)
   pic_defun(pic, "nan?", pic_number_nan_p);
   pic_gc_arena_restore(pic, ai);
 
+  pic_defun(pic, "=", pic_number_eq);
+  pic_defun(pic, "<", pic_number_lt);
+  pic_defun(pic, ">", pic_number_gt);
+  pic_defun(pic, "<=", pic_number_le);
+  pic_defun(pic, ">=", pic_number_ge);
   pic_defun(pic, "abs", pic_number_abs);
 
   pic_defun(pic, "floor-quotient", pic_number_floor_quotient);