Søren Kierkegaard understood dread (anxiety) to have a dual aspect

1. The extraordinarily crushing weight of making a free choice

2. The potent thrill of making a free choice

It is in the tension created by these opposing forces that we find ourselves. The scenario described on the home page speaks to this dual aspect. Standing on the edge of the cliff and peering over one finds their freedom, their ability to truly choose their next step (forward to imminent death or back to live another day). Either choice is utterly complete and final; the consequences for the decision eternally bound to the person in that moment.

Dread (anxiety) is distinguished from fear. Fear reveals to us some part of the world that is threatening, dangerous to us (e.g. that giant spider may strike me, push venom, and wrap my body in webbing in order to feast on my liquified innards). Dread, while sharing the sense of being threatened, has no specific target (e.g. dread is not of some specific "thing". The threat is more broad, encompassing our very existence). When fully embraced, dread functions to withdraw us from our common day to day sense of self, who we are. It strips us of our usual ways of thinking about ourselves as having roles and projects in the world. Once we are pulled away from these common ways of thinking we are better able to see ourselves authentically. Imagine being forced to "walk the plank", not out over water, but into a void. Being forced away from how we casually think of ourselves and then turning back to see one's whole self revealed. To be free we must seek our own most possibility and in order to authentically see our possibilities (i.e. not those that are common to all, but what is unique to each of us) we must strip away the common ways of understanding ourselves and that is the function of dread.

By Heidegger's reckoning death performs a crucial function that is necessary for us to have any being whatsoever (i.e. we could not exist without death). The idea is this: what constitutes our being is not only our present moment, but also the entirety of our future possibilities. However, should this set of possibilities run on endlessly then there would never any particular set of possibilities that would make us an actual, existing entity.

A clarifying example is needed after that word salad: imagine an author working on a book (perhaps someone like George R. R. Martin). If the author just keeps going on and on, writing and editing, doing whatever, but never actually finishes the book, then there will simply not be a book. Or another example: if you are writing a word, but the word is spelled with an infinite set of letters then that word will never actually be written, the attempt at writing it will just go on and on. In short, for something to actually become it has to have an end. Death is our end. Death throws us back onto our selves, limiting us, and allowing us to actually become a real entity. Death is the end of our book, the end of our word, that allows us to actually have some meaning in reality.