diff --git a/copycat/conceptMapping.py b/copycat/conceptMapping.py
index 24514f5..c089045 100644
--- a/copycat/conceptMapping.py
+++ b/copycat/conceptMapping.py
@@ -79,6 +79,7 @@ class ConceptMapping(object):
     def sameDescriptors(self, other):
         if self.sameInitialDescriptor(other):
             return self.sameTargetDescriptor(other)
+        return False
 
     def sameKind(self, other):
         return self.sameTypes(other) and self.sameDescriptors(other)
@@ -87,10 +88,10 @@ class ConceptMapping(object):
         return self.sameTypes(other) and self.sameInitialDescriptor(other)
 
     def isContainedBy(self, mappings):
-        return any([self.sameKind(mapping) for mapping in mappings])
+        return any(self.sameKind(mapping) for mapping in mappings)
 
     def isNearlyContainedBy(self, mappings):
-        return any([self.nearlySameKind(mapping) for mapping in mappings])
+        return any(self.nearlySameKind(mapping) for mapping in mappings)
 
     def related(self, other):
         if self.initialDescriptor.related(other.initialDescriptor):
@@ -136,10 +137,12 @@ class ConceptMapping(object):
     def relevant(self):
         if self.initialDescriptionType.fully_active():
             return self.targetDescriptionType.fully_active()
+        return False
 
     def slippage(self):
         if self.label != slipnet.sameness:
             return self.label != slipnet.identity
+        return False
 
     def symmetricVersion(self):
         if not self.slippage():
diff --git a/copycat/rule.py b/copycat/rule.py
index ba741ec..2618e37 100644
--- a/copycat/rule.py
+++ b/copycat/rule.py
@@ -91,8 +91,8 @@ class Rule(WorkspaceStructure):
         if correspondence.objectFromInitial != changed:
             return False
         # it is incompatible if the rule descriptor is not in the mapping list
-        return bool([m for m in correspondence.conceptMappings
-                     if m.initialDescriptor == self.descriptor])
+        return any(m.initialDescriptor == self.descriptor
+                   for m in correspondence.conceptMappings)
 
     def __changeString(self, string):
         # applies the changes to self string ie. successor
diff --git a/copycat/slipnet.py b/copycat/slipnet.py
index 062d53d..17194f7 100644
--- a/copycat/slipnet.py
+++ b/copycat/slipnet.py
@@ -35,7 +35,8 @@ class SlipNet(object):
 
     def setConceptualDepths(self, depth):
         logging.debug('slipnet set all depths to %f', depth)
-        _ = [node.setConceptualDepth(depth) for node in self.slipnodes]
+        for node in self.slipnodes:
+            node.setConceptualDepth(depth)
 
     def reset(self):
         logging.debug('slipnet.reset()')
@@ -49,8 +50,10 @@ class SlipNet(object):
         logging.debug('slipnet.update()')
         self.numberOfUpdates += 1
         if self.numberOfUpdates == 50:
-            _ = [node.unclamp() for node in self.initiallyClampedSlipnodes]
-        _ = [node.update() for node in self.slipnodes]
+            for node in self.initiallyClampedSlipnodes:
+                node.unclamp()
+        for node in self.slipnodes:
+            node.update()
         for node in self.slipnodes:
             node.spread_activation()
         for node in self.slipnodes:
diff --git a/copycat/slipnode.py b/copycat/slipnode.py
index e97cbf9..c457bab 100644
--- a/copycat/slipnode.py
+++ b/copycat/slipnode.py
@@ -13,7 +13,7 @@ def jump_threshold():
 
 def points_at(links, other):
     """Whether any of the links points at the other"""
-    return any([l.points_at(other) for l in links])
+    return any(l.points_at(other) for l in links)
 
 
 class Slipnode(object):
@@ -124,8 +124,7 @@ class Slipnode(object):
                         for l in self.outgoingLinks if l.label == relation]
         if destinations:
             return destinations[0]
-        node = None
-        return node
+        return None
 
     def getBondCategory(self, destination):
         """Return the label of the link between these nodes if it exists.
@@ -150,13 +149,13 @@ class Slipnode(object):
 
     def spread_activation(self):
         if self.fully_active():
-            _ = [link.spread_activation() for link in self.outgoingLinks]
+            for link in self.outgoingLinks:
+                link.spread_activation()
 
     def addBuffer(self):
         if self.unclamped():
             self.activation += self.buffer
-        self.activation = min(self.activation, 100)
-        self.activation = max(self.activation, 0)
+        self.activation = min(max(0, self.activation), 100)
 
     def can_jump(self):
         if self.activation <= jump_threshold():
diff --git a/copycat/workspaceObject.py b/copycat/workspaceObject.py
index 981262d..1aeee62 100644
--- a/copycat/workspaceObject.py
+++ b/copycat/workspaceObject.py
@@ -161,7 +161,7 @@ class WorkspaceObject(WorkspaceStructure):
         return False
 
     def described(self, slipnode):
-        return bool([d for d in self.descriptions if d.descriptor == slipnode])
+        return any(d.descriptor == slipnode for d in self.descriptions)
 
     def middleObject(self):
         # only works if string is 3 chars long