diff --git a/src/function/builtin/cons/LENGTH.java b/src/function/builtin/cons/LENGTH.java
index ca1270e..2acade0 100644
--- a/src/function/builtin/cons/LENGTH.java
+++ b/src/function/builtin/cons/LENGTH.java
@@ -3,6 +3,7 @@ package function.builtin.cons;
 import static function.builtin.cons.LIST.makeList;
 import static recursion.TailCalls.done;
 import static recursion.TailCalls.tailCall;
+import static table.FunctionTable.lookupFunction;
 
 import java.math.BigInteger;
 
@@ -17,12 +18,15 @@ import sexpression.LispNumber;
 public class LENGTH extends LispFunction {
 
     public static BigInteger getLength(Cons list) {
-        LENGTH lengthFunction = new LENGTH("LENGTH");
-        LispNumber length = lengthFunction.callWithoutArgumentValidation(makeList(list));
+        LispNumber length = lookupLength().callWithoutArgumentValidation(makeList(list));
 
         return length.getValue();
     }
 
+    private static LENGTH lookupLength() {
+        return (LENGTH) lookupFunction("LENGTH");
+    }
+
     private ArgumentValidator argumentValidator;
 
     public LENGTH(String name) {