I've always been interested in the reasonable logical approach Sagan gave to complex issues. I used to read a lot of Arthur C Clarke and I reckon I first found him through that, as a teenager.

Incidentally, I use a quote from him occasionally. I have a presentation I use when teaching, giving an introduction in how to improve healthcare. Many students want to rush in and redesign the wheel, so after my into talk, I forward to the next slide whilst we debate how to improve services.

The slide says;

"If you want to make an apple pie from scratch, you must first create the universe."
Carl Sagan