Why TCS?

The summer school in Finland (SADA) was fun. Lot of great lectures (Piotr, Nir, Lars, Paolo and alas, I missed Aris's lectures since he started after I left). I had to squeeze my lectures into M-W so I am not away too much. Lots of students (70+), most in 2nd year of PhD, preped and ready for research problems. The students came from all over Europe, in some cases, Israel, Canada and Asia, and from different backgrounds. I asked them why they were doing their PhD in theory, and in almost all the cases, the answer was that they wanted something concrete, clear, correct and (close to?) the truth. That is, what attracts them is the math of CS.