Descartes' mechanistic vision, and our whole body of scientific knowledge, is based on the taking apart the objects and phenomena of nature. In orde to understand the electron, scientists had to begin putting the parts nack togehter. Electrons do not really exist as solid matter. The electrons that make up material things are simply a web of interactions, each responding to and effecting the others. Systems theory is the new way of viewing nature that has evolved to interpret this type of interdependent phenomena.
Systems theory tries to look at interaction and cycles that ocurr in nature.
It is an attempt to take what Cartesian science can teach us and synthesis it into a synergistic picture of reality. This evolution in thinking is interesting becuase it started by looking at ever smaller pieces of nature, all the way down to the electron, and now it is growing back outwards to encompass our entire planet. Perhaps systems thinkers will continue to expand their integrated view of reality until they encompass the whole universe in one gaint system of life. Maybe they will go a step further in reversing Cartesian thinking and reconnect religious experience to science. This would be impossible if considered through the old ways of thinking about these two subjects, and indeed it seems inconcievable to all of us who have been raised in the current way of thinking.