When you are falling in love, everything feels different. You can't wait to you see her (him) again. Actually you want to be with her (him) all the time. You are plain happy.
When you get married, you are in love. But life has a habit of getting in the way. Where are we going to live? Who will do the dishes? How about the laundry? Who will take off time for the plumber? Now throw in kids. Are you pushing the kids too much? Is she (he) too "American" with them? Crises happen. But, you're still in love. You remember the real her (him), your first kiss, your first candle light dinner, your first trip away in your little beat-up car. And that is, what holds a marriage together.
Wanting to go into research in programming languages must feel like falling in love. Working on your PhD is going to be much more like being in love. So, as you are about to embark on your PhD studies (or wondering whether you should), I suggest you keep this analogy in mind. To explain why, my keynote will illustrate the analogy with one research theme---adding types to dynamic languages---that I have pursued for 30 years.