So why do I make the connection? Well:

1. From complexity theory we get two important insights: Firstly complex systems are highly sensitive to small changes in initial conditions and secondly the agents are both constrained by and in turn constrain the system of which they are a part.
2. From existentialism we get the concept that we make choices, and we have to take responsibility for those choices. We become by being, by enacting in the world and also, in Sartre's later thinking as he took a more humanistic approach some of those choices can be right or wrong.

If we look at the unfolding aspect of our interlinkings with the networked world then we can see aspects of both of these summaries. A single blog, if picked up and amplified can accelerate to constrain the press. Equally we fit within cultural norms. We are constrained by, and in terms constrain the system. We can also make choices, I have never bought strict determinism. When we decide to take a job, leave a job, say something in the goldfish bowl of the blogosphere we make choices. One of the values of the network is that we cannot hide behind anonymity or a closed community (my one reference to Jerry this morning), what we do is visible and influential even in small ways.

Given that system constraints, when they happen result from a rapid coalescence within a complex system (often catastrophic) as something passes a tipping point (think of Apple Mac against the IBM PC, Betamax against Videotext and others for technology adoption) we will never have the luxury of much reflection. The world continues to unfold and multiple actions/choices influence that path. The system does not stand still. This is one of the key insights of the Clue Train Manifesto: things just happen faster, our choices are more rather than less important and we have no excuse as to the availability of information or knowledge of consequences.

From a personal point of view the earlier referenced link to literature is ironic. Many years ago now, when I was student representative to the Philosophy Faculty at Lancaster University, I proposed that we should have a course on Existentialism, Professor Sibley looked at me with distain and said: If you want to study European Literature then you need to change departments. This was the height of the analytic period and Sibley and I were already in dispute over the nature of aesthetics. I wanted to discuss concepts such as beauty, truth and the like. Sibley wanted to discuss what it meant when a critic said something was beautiful by analyzing the text of their criticism. We had a troubled relationship. One of the other major debates in the 70's was the separation of politics and religion, many of us argued then that separating the two (generally used as a means of avoiding responsibility of the slums of Rio, the Vietnam war or Apartheid) was not possible, as to do so was to make a choice. In an evolving, unfolding landscape you can not stand aside and claim not to avoid responsibility; a sin of omission is not less serious than one of commission. We are the means by which we create meaning, our choices (or lack of choice) are a part of the unfolding pattern of the world in which we live and we need to take responsibility for them, that way lies freedom.

For Kierkegaard, who can probably be considered the founder of existentialism (although I would trace elements back to Aquinas and even Socrates) the nature and consequences of this freedom lead to dread. For Marcel Gabriel this realisation was characterised by a need for mutual fidelity and hope. I think the connectivity of which we are all a part should, hopefully (sic) bring us closer to Gabriel than to Kierkegaard. Marcel's fear of the annihilation of a sense of human mystery by a focus on technology and problems/solutions should also be a warning to us.