diff --git a/pyreason/scripts/facts/fact_edge.py b/pyreason/scripts/facts/fact_edge.py
index bbeb3e64..313cee97 100755
--- a/pyreason/scripts/facts/fact_edge.py
+++ b/pyreason/scripts/facts/fact_edge.py
@@ -8,6 +8,7 @@ def __init__(self, name, component, label, interval, t_lower, t_upper, static=Fa
         self._label = label
         self._interval = interval
         self._static = static
+        self.static = static
 
     def get_name(self):
         return self._name
diff --git a/pyreason/scripts/facts/fact_node.py b/pyreason/scripts/facts/fact_node.py
index 69e379eb..d86e7db5 100755
--- a/pyreason/scripts/facts/fact_node.py
+++ b/pyreason/scripts/facts/fact_node.py
@@ -8,6 +8,7 @@ def __init__(self, name, component, label, interval, t_lower, t_upper, static=Fa
         self._label = label
         self._interval = interval
         self._static = static
+        self.static = static
 
     def get_name(self):
         return self._name
diff --git a/pyreason/scripts/interval/interval.py b/pyreason/scripts/interval/interval.py
index 18d25ede..4769a16a 100755
--- a/pyreason/scripts/interval/interval.py
+++ b/pyreason/scripts/interval/interval.py
@@ -4,7 +4,17 @@
 
 
 class Interval(structref.StructRefProxy):
-    def __new__(cls, lower, upper, s=False):
+    def __new__(cls, lower, upper, s=False, *args):
+        if len(args) == 2:
+            prev_lower, prev_upper = args
+            obj = object.__new__(cls)
+            obj.l = lower
+            obj.u = upper
+            obj.s = s
+            obj.prev_l = prev_lower
+            obj.prev_u = prev_upper
+            return obj
+
         return structref.StructRefProxy.__new__(cls, lower, upper, s, lower, upper)
 
     @property
@@ -66,7 +76,7 @@ def intersection(self, interval):
         if lower > upper:
             lower = np.float64(0)
             upper = np.float64(1)
-        return Interval(lower, upper, False, self.lower, self.upper)
+        return Interval(lower, upper, False)
 
     def to_str(self):
         return self.__repr__()
diff --git a/pyreason/scripts/numba_wrapper/numba_types/interval_type.py b/pyreason/scripts/numba_wrapper/numba_types/interval_type.py
index 3d34b77d..28d6448e 100755
--- a/pyreason/scripts/numba_wrapper/numba_types/interval_type.py
+++ b/pyreason/scripts/numba_wrapper/numba_types/interval_type.py
@@ -142,4 +142,4 @@ def impl(interval_1, interval_2):
 
 @njit
 def closed(lower, upper, static=False):
-    return Interval(np.float64(lower), np.float64(upper), static, np.float64(lower), np.float64(upper))
+    return Interval(np.float64(lower), np.float64(upper), static)