diff --git a/src/Life.java b/src/Life.java
index ab76c40..a7a55fd 100644
--- a/src/Life.java
+++ b/src/Life.java
@@ -46,6 +46,9 @@ public class Life implements ILife {
 
   @Override
   public void setAlive(int x, int y) {
+    if (isInBounds(x, y)) {
+      grid[x][y] = true;
+    }
   }
 
   @Override