If you had the chance to bring someone back alive, who would it be and why?

I would probably bring back Albert Einstein. It's obviously remarkable how many relevant scientific contributions he was able to make all those years ago having little to no technology and hardly anyone comparably knowledgeable to bounce his ideas off of. I believe if we were able to bring him back to life, and set him up with some of the technology and scientists we have now, he could help make life altering discoveries to help save and improve our planet.