Nobody knows why moths are attracted to light

I was watching QI the other day and there is often a a fact on the show to which nobody knows the answer. The episode I was watching the other night revealed that science is yet to answer the reason why moths are attracted to light. This surprised me because it is such a common thing to see a moth flying towards a light, I thought, surely some scientist would have tried to discover the answer, and many probably have, which is why even without a definitive answer there are still many theories as to the explanation. I however I am happy that this fact is still a mystery because it hopefully means that scientists have spent their time on discovering more worthy scientific answers. 

As far as theories go however, I think that the comedian Jimeoin has the best theory, which is not remotely based in scientific fact. His theory is linked to reincarnation, you know how you often hear about people having near death experiences and they talk about walking towards the white light. Jimeoin's theory is that before people die they walk towards the white light, and when they pass through the white light, they die and are then reincarnated as a moth. So the first thing they remember as a moth is walking towards the white light in their previous life, so as a moth they want to get back through the white light to their original life. Thus explaining why all moths are attracted to the light, they are trying to reverse their reincarnation. Now maybe there is a scientific theory out there with more basis in science than Jimeoin's, but I am not really interested, because until they can tell me with absolute certainty the reason, I am happy to believe Jimeoin!