diff --git a/2021/day12.hs b/2021/day12.hs
index 03d61c3..c605f1e 100644
--- a/2021/day12.hs
+++ b/2021/day12.hs
@@ -12,8 +12,6 @@ readPath s = (from,to) where [from,to] = splitOn "-" s
 addPath :: Path -> System -> System
 addPath (from,to) = unionWith (++) (Data.Map.fromList [(from,[to]), (to,[from])])
 
-isLower :: String -> Bool
-isLower = Data.Char.isLower . head
 isUpper :: String -> Bool
 isUpper = Data.Char.isUpper . head
 
@@ -40,4 +38,4 @@ main = do
 
     putStrLn "part 2: "
     let paths = map reverse $ pathFinder2 system ["start"] 
-    print $ length paths
\ No newline at end of file
+    print $ length paths