diff --git a/src/com/annimon/everlastingsummer/Lexer.java b/src/com/annimon/everlastingsummer/Lexer.java
index 610a612..c81d43e 100644
--- a/src/com/annimon/everlastingsummer/Lexer.java
+++ b/src/com/annimon/everlastingsummer/Lexer.java
@@ -54,6 +54,7 @@ public final class Lexer {
         KEYWORDS.put("if", TokenType.IF);
         KEYWORDS.put("else", TokenType.ELSE);
         KEYWORDS.put("endif", TokenType.ENDIF);
+        KEYWORDS.put("not", TokenType.NOT);
         
         KEYWORDS.put("renpy.pause", TokenType.RENPY_PAUSE);
         KEYWORDS.put("persistent.sprite_time", TokenType.PERSISTENT_SPRITE_TIME);
diff --git a/src/com/annimon/everlastingsummer/Parser.java b/src/com/annimon/everlastingsummer/Parser.java
index c9f1a08..fea8065 100644
--- a/src/com/annimon/everlastingsummer/Parser.java
+++ b/src/com/annimon/everlastingsummer/Parser.java
@@ -412,6 +412,13 @@ public final class Parser {
     }
     
     private Expression expression() {
+        return notTest();
+    }
+    
+    private Expression notTest() {
+        if (match(TokenType.NOT)) {
+            return new ValueExpression( notTest().eval() != 0 ? 0 : 1 );
+        }
         return equality();
     }
     
@@ -459,9 +466,6 @@ public final class Parser {
         if (match(TokenType.PLUS)) {
             return primary();
         }
-        if (match(TokenType.EXCL)) {
-            return new ValueExpression( primary().eval() != 0 ? 0 : 1 );
-        }
         return primary();
     }
     
diff --git a/src/com/annimon/everlastingsummer/TokenType.java b/src/com/annimon/everlastingsummer/TokenType.java
index 3e17aeb..7fcaf25 100644
--- a/src/com/annimon/everlastingsummer/TokenType.java
+++ b/src/com/annimon/everlastingsummer/TokenType.java
@@ -52,6 +52,7 @@ public enum TokenType {
     IF,
     ELSE,
     ENDIF,
+    NOT,
     
     // команды
     RENPY_PAUSE,