"The world has never faced a problem like this. Without massive mitigation more than a decade before the fact, the problem will be pervasive and long-lasting. Previous energy transitions (wood to coal and coal to oil) were gradual and evolutionary; oil peaking will be abrupt and discontinuous."
Summary of formal report prepared for the US government by Robert Hirsch and others, Spring 2005, available here.
The issue is not the theoretical viability of human society and civilisation in the absence of fossil fuels. That is possible with existing technology - by and large.
The issue is the transition from one state to another state - the phase transition. I can't see anyway in which that transition can be accomplished without a significant loss of utilised energy in the system as a whole.
Let me translate that into something less obscure: the system using abundant and cheap energy supports a certain population; the system using scarce and expensive energy will support a much lower population. The transition is going to be painful, and we need to begin planning for that transition now.
Which makes me think about small scale power stations for Mersea Island - a tidal barrage?
Actually, what I think most necessary is the strengthening and building up of community. People working together provides much more than the agglomeration of individuals. That also has the benefit of not being futile endeavour should all these fears prove misplaced...