We know things are changing - faster than we would like maybe. Climate change, peak oil, resource depletion, population growth, technology changes, economic booms and busts, all contribute to a less than certain age. Many of these challenges seem beyond our control.
However, the way we think about them, and how we react as individuals, groups, organisations and networks, is under our control.
The other strand to this principle is planning and designing for known changes. For example, seasons of spring, summer, autumn and winter are predictable and can be planned for, and incorporated into our designs, management and action plans. How eco-systems change over time - in ecology this is called 'succession' is also predictable, at least overall. By understanding how ecosystems change over time, we can accelerate the process and create productive ecosystems faster than is usual in nature. Forest gardens are an example of this, where all the layers of the forest are put in all in one go, rather than over many years.
There are also many methods for social change, organisational development and community engagement that we can use to help groups work together and collectively plan for changes. Working with people is just as important in permaculture as working with plants (which are much easier!)