As of now, string theorists have no explanation of why there are three large dimensions as well as time, and the other dimensions are microscopic. Proposals about that have been all over the map.

1/r^2 has a nasty singularity at r=0, but it did not bother Newton-the Moon is far enough.

String theory is an attempt at a deeper description of nature by thinking of an elementary particle not as a little point but as a little loop of vibrating string.

I have a tendency, more than most other physicists, to try to figure out everything all at once, before I publish. And even to try to figure out everything in my head, without pencil and paper.

I have a much easier time imagining how we would understand the big bang, even though we can't do it yet, than I can imagine understanding consciousness.

Quantum mechanics brought an unexpected fuzziness into physics because of quantum uncertainty, the Heisenberg uncertainty principle. String theory does so again because a point particle is replaced by a string, which is more spread out.

String theory is 21 st century physics that fell accidentally into the 20th century.