>For me, when I have good life-experiences, and think about them (which I do almost constantly), it just makes me look all the more eagerly to see what neat new thing is coming next. It doesn't stop my motivation to achieve.

Yes you think about them and it inspires you try to achieve another good experience or maybe you are lucky and another good one just comes along. Thinking is significantly different to feeling. The point is that you can't feel it all over again and really re-live it, it is elusive, the actual feeling itself is very short lived. Try as hard as you will you won't be able to re-capture it (at the same level of intensity). Maybe if we could command our bodies to do that then we might never feel the need to achieve anything anymore.

I'd love to know of anyone can actually re-feel something. Perhaps it is possible.