Emergence is the process of complex pattern formation from simpler rules.
This can be a dynamic process (occurring over time), such as the evolution of the human body over thousands of successive generations; or emergence can happen over disparate size scales, such as the interactions between a great number of neurons producing a human brain capable of thought (even though the constituent neurons are not individually capable of thought). The original term was “categorial novum” coined by Nicolai Hartmann.
For a phenomenon to be termed emergent it should generally be unpredictable from a lower level description. At the very lowest level, the phenomenon usually does not exist at all or exists only in trace amounts: it is irreducible. Thus, a straightforward phenomenon such as the probability of finding a raisin in a slice of cake growing with the portion-size does not generally require a theory of emergence to explain. It may, however, be profitable to consider the “emergence” of the texture of the cake as a relatively complex result of the baking process and the mixture of ingredients. (Wikipedia)
The article gives this example of an emergent property:
The complex behaviour or properties are not a property of any single such entity, nor can they easily be predicted or deduced from behaviour in the lower-level entities: they are irreducible. No physical property of an individual molecule of air would lead one to think that a large collection of them will transmit sound. The shape and behaviour of a flock of birds or school of fish are also good examples.
If this is making you scratch your head in bewilderment, read on. We’ll apply gross simplification to this elegant but confusing idea.
Most of us are really fond of a predictable world. 1 + 1 = 2. The ease and repeatability of the equation give us the illusion of stability. One of the most interesting aspects of our world is that sometimes,
1 + 1 = Rhinoceros
In other words, some times, more of the same makes for something really different. This is the case that the voices who decry the use of metrics in blogging are making. Somehow, Blogging creates a universe that ought not be measured lest the magic be taken away. If we measure our blogs, they say, evil will happen and 1 + 1 will only equal 2. That will be the fault of the people who wish to measure things.
There doesn’t appear to be much evidence that a cake changes texture when you measure it or that air carries less sound because you monitor its temperature. Emergent behavior happens whether or not you keep metrics on the basic stuff. In fact, you can measure the capacity for air to carry sound. That doesn’t seem to impair the air.
This is the deep end of a long argument. We’re not saying that there’s no magic to be found in blogging. There is. The more of it, the more interesting things get. There may well be emergent properties galore that come for the widespread use of interactive serial communications.
We’re also not saying that you can measure the magic. You can’t. The number of units shipped does not measure the joy a customer gets. A newspaper’s circulation is not a measure of its influence. The number of CDs sold doesn’t touch the number of hours of pleasure derived. The number of books sold is unrelated to the number of books read. And on and on.
You need measurement for conversation. It’s funny that the advocates of metric free blogging all point to the value of conversation. Metrics (or shared precise language) are a necessary part of any substantial conversation. Facts, figures and evidence (the stuff of metrics) make for long term shared conversations that are not arm waving.
They help you avoid passive aggressive behavior like “If you try to measure me, I’ll stop writing the blog.”