what does the word locomotive mean

Van Gogh began his work influenced by the Dutch Masters. He was intrigued by the Masters' power to enjoy shadow and light-weight. He also found an association inside painting of common events and/or people. For instance, The Potato Eaters captures several peasants seated for any meal. The painting is dark, yet, light radiates from the faces. The story shocked me more than usual because I know my friend is a fairly good martial artist. He is often dubbed as 'talented' by his colleagues and superiors. What's wrong with this story? In theory, he may have wasted the thief quickly while he clearly had no weapon with him. According to him, he didn't know what to do. He knew how he could subdue such assault but he just did not know how to handle it at that time.