So you think you want to do a PhD?

Working on a PhD is not for everyone. It is a low-paid job. It is difficult. You do not get adequate instructions on what to do or how to do it. You will be subjected to many time-consuming interruptions and distractions from your main work. Other people will have only a superficial understanding of what you are doing. The combination of all these factors will make you extremely frustrated and stressed at times, and you will suffer from uncertainty about your abilities, about the quality of your work, and about your future. Depression is likely. In spite of these difficulties, you will need to be able to demonstrate that you are making clear and interesting progress. Throughout your time as a PhD student, you will need to give talks about your achievements to various audiences, and write papers for extremely critical audiences. There are high expectations, and few affirmations of the value of your work. You will be expected to develop (on your own) and apply several skills, including:

• You are expected to be able to learn new topics on your own, by reading papers and books, rather than by attending classes.
• You are expected to be able to identify fundamental questions, and to figure out what small concrete steps (taking only months or weeks) can be taken now which are clearly headed towards answering the fundamental questions.
• You are expected to be able to study a specific area in depth, finding relevant papers on a given topic and coming to an understanding of the current state of that subfield.
• You are expected to have the technical skills necessary to solve the problems that arise in the course of your work, and to learn new technical skills as needed.
• You are expected to be able to communicate with others both at a technical level (i.e., the details of your project -- this is the easy part, because you know what you are doing), and at a high level (i.e., how the ideas behind your projects relate to other work currently being done in the rest of the world -- this is the hard part, because it requires knowing what everyone else in the world is doing), both in speaking and in writing.
• You are expected to be self-motivated and self-sufficient. Everyone around you will be busy, and only able to help you in small ways. Most of your work, including types of things you have never done before, will need to be done and double-checked just by you, to a level that can withstand very critical inspection by experts. You will have to figure out on your own how to do these things well.

Another issue is that you will be stuck with your advisor for several years. You need to personally get along well with your advisor and their style of supervision. You should evaluate this honestly and talk with other students of the advisor you are considering. If the advisor is very hands-on, or very hands-off, or usually out of town, or critical, or uncritical, or tells you exactly what to do, or doesn't tell you at all what to do, or is extremely methodical, or completely disorganized -- is this compatible with how you are most productive? Do the students in the group take an active interest in each other's projects? Contrary to what you might expect, it is very difficult or impossible to change advisors after you start.

As one very good student said at the end of their PhD, "I know you listed all these problems on that web page, but I just didn't believe it. You need to add that it's really true!" So there you have it: It's really true! In fact these warnings are written mainly for the good students, who are used to things being easier than advertised. This is not easier than advertised. The frustrations and self-doubt described above are what happens to the good students.

I say all of this because I see many people who choose to be a PhD student simply because it seems natural to them to continue going to school, as they have been doing all their life. These students seem to be on "autopilot", with little awareness of why they have chosen this path over the alternatives, and often it seems they have not made the right choice. If you choose to be a PhD student, you should be aware that it is completely different from any kind of school you have gone to, and for most career paths, it is not the optimal choice to make. Think about what you are doing and why.

Still interested?
If many of the "difficulties" listed above actually sounded to you like freedom and opportunity accompanied by self-evident responsibilities, and you have a strong internal drive to find answers to current questions of science, then a PhD may be just right for you. You will be around many other students that you can ask for advice and opinions. When you are done, you will be ready (among other things) to create and direct successful projects on your own, with nobody telling you what to do. This will open the door to the extremely competitive, low paid positions that academia can offer.