It depends what motivates you and where you want to be in 4 years. There are far easier ways to earn money in the long term than doing a PhD. A PhD gives you 4

It depends what motivates you and where you want to be in 4 years. There are far easier ways to earn money in the long term than doing a PhD. A PhD gives you 4 years* of relative freedom to build yourself intellectually within some rough bounds (these bounds are dependent on your program and can be quite tight though). You also get to hang out on campus with other PhDs (ymmv!). But, you could get similar freedom with even less bounds by working and saving hard for the next 4 years and then doing what you want. It depends what motivates you. *depends where you are though. I'm UK.