Yeah, this is my favourite topic, no wonder it's topic of my thesis, too. I read a lot of stuff so I could choose the basic that you have to keep in your mind! My most favourite rule, the slide with sandglass, could tell you, that everything you want to do and do begins with awareness of your own death. Imagine your own funeral - what do you want to your family member, your friend and your co-worker say about you?
Clipping is a handy way to collect important slides you want to go back to later.