Why is e^pi i = -1 weird? B/c we think of exp as e^x -- an exponential function. This form makes sense for integers w/o problem, rationals with some work, and reals by continuity. However, what does 2^i mean? (Or e^i?) It's simply meaningless -- we get e^z by expanding a power series, and plugging in complex numbers. [NB: no analytic continuation issues.] That's why it's -weird- -- our original interpretation doesn't make sense any more. Once you understand exp geometrically (say, as a covering space of lie groups), then it's really obvious -- and you see that e^(x+y) = e^x * e^y is the key property that guarantees that it behaves like 2^x etc. for reals. [& why does the imaginary axis wrap around the circle? look at d(exp) at z=0 -- imaginary derivative better point -up-]