diff --git a/history/003a_legs/src/main/java/com/github/drinkjava2/frog/brain/organ/LogicNot.java b/history/003a_legs/src/main/java/com/github/drinkjava2/frog/brain/organ/LogicNot.java
new file mode 100644
index 0000000..6e5587c
--- /dev/null
+++ b/history/003a_legs/src/main/java/com/github/drinkjava2/frog/brain/organ/LogicNot.java
@@ -0,0 +1,32 @@
+/*
+ * Copyright 2018 the original author or authors. 
+ * Licensed under the Apache License, Version 2.0 (the "License"); you may not
+ * use this file except in compliance with the License. You may obtain a copy of
+ * the License at http://www.apache.org/licenses/LICENSE-2.0 Unless required by
+ * applicable law or agreed to in writing, software distributed under the
+ * License is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS
+ * OF ANY KIND, either express or implied. See the License for the specific
+ * language governing permissions and limitations under the License.
+ */
+package com.github.drinkjava2.frog.brain.organ;
+
+import com.github.drinkjava2.frog.Frog;
+import com.github.drinkjava2.frog.brain.Organ;
+
+/**
+ * LogicAnd has a "NOT" logic, i.e. if any cells active it, it doesnot active,
+ * if no cell active it, it active
+ * 
+ * 非门
+ */
+public class LogicNot extends Organ { // 随意布置一些"非门"在脑里,至于能不能被选中，就听天由命了
+	private static final long serialVersionUID = 1L;
+
+	@Override
+	public void active(Frog f) {// 非门的逻辑最简单，如果它被激活，则没有输出，如果它没被激活，则输出信号
+		if (activedByCells(f))
+			return;
+		activeOtherCells(f);
+	}
+
+}