Hmm..
So you should accept that nothing is forever and to avoid allowing yourself to become affected by it when it inevitably ends, when all along you knew it would end, and you allowed yourself to become deluded that it might be otherwise.
That seems like a pretty sensible way to live your life.
My system seems to work on a level below that.. Rather than seeing through and understanding that, as a reason not to become affected, you should not become affected because allowing yourself to become consumed by negative emotions is unproductive, and is pointless when you have a choice over how you feel, and you may as well choose to feel positive, which you enjoy, than negative, which you do not.
Throw in some degree of 'for the greater good' and you've got pretty much how I think.