The dictionary has not helped you understand the meaning of "indulge" by using the word "involve", which has a quite different meaning. It's a very bad definition, I'm sorry to say. See this definition. http://www.collinsdictionary.com/dictionary/english-cobuild-learners/indulge?showCookiePolicy=true The example sentences in the link are good ones. Try making up your own sentence and we can tell you if it's good.