Early ecologists soon realised that, since humans are organisms, ecology should include the study of the relationship between humans and the rest of the biosphere. ... We don't often tend to think about the social sciences (history, economics and politics) as subcategories of ecology. But since people are organisms, it is apparent that we must first understand the principles of ecology if we are to make sense of the events in the human world.

When we decline to talk about what is real simply because it's uncomfortable to do so, we seal our own fate.

All of the easy oil is gone and what's left is requiring more energy and money and this has an effect on everything. Our problem is that we've created an infrastructure that's so dependent on oil. As oil becomes more expensive we're going to be locked into the transportation modes that our economy depends on. So we really need to start building an alternative economy before we get caught in a trap of our own making.

Surveying the available alternative energy sources for criteria such as energy density, environmental impacts, reliance on depleting raw materials, intermittency versus constancy of supply, and the percentage of energy returned on the energy invested in energy production, none currently appears capable of perpetuating this kind of society.

What's new is high oil prices and the economy hates high oil prices.

The real problem is that we use too much oil. It's that simple and that difficult. If we truly want to reduce our vulnerability to high prices, the best way to do so is to reduce consumption.

We are about to enter a new era in which, each year, less net energy will be available to humankind, regardless of our efforts or choices. The only significant choice we will have will be how we adjust to this new regime. That choice - not whether, but how to reduce energy usage and make a transition to renewable alternatives - will have profound ethical and political ramifications.