I do not think you can name many great inventions that have been made by married men (Nikola Tesla). I’m not sure how to test the validity of this observation. I guess we could start by defining great inventions and then checking to see if the inventors were married or single. Part of me, without even checking, believes this saying to be true. It’s not that smart men don’t marry. I think it has more to do with priorities and decisions about use of time and resources. Any married person (male or female) or any person in a committed relationship knows that the relationship becomes the primary focus instead of each individual’s priorities. In a relationship, the pursuits by either partner are determined by what ultimately benefits the relationship as a whole (which then benefits the individuals involved). Inventions, I would think, take time, money, and great personal sacrifice to pursue. Perhaps this type of total dedication to a project would be less likely in a committed, long-term relationship. Relationships take time, energy, and effort to maintain and nurture. Divided loyalties, regardless of what they are, will dilute the quality of either loyalty involved. There probably are people who have succeeded in many ways while married. On the other hand, did these married people accomplish all they could have accomplished if part of their time and resources were not diverted to another party or priority? I don’t know. I really don’t. I remember reading once about Kathrine Hepburn saying that a woman really does have to choose between being a parent or having a career. She did not say it’s not possible to do both at the same time, she just said you would not be great at either one if you tried to do both. There may be some truth to it. As I raised my three children, I truly thought I was doing a great job of being a parent as well as doing a great job as a social worker. In the end (when they were all grown) they have informed me (in so many words) that I was, in fact, a crappy parent in their eyes. It remains to be seen if I am a great social worker or a crappy one. It depends on the day and who you ask I think.