To add to the previous answers that treat specifically of the biological Darwinism, there is also Universal Darwinism which postulates that evolution is a natural phenomenon that appears when a set of conditions and constraints are present. And indeed, it has succesfully been applied to a number of fields (see below the quote), which seems to imply that evolution is not a property of the evolving individuals (as you implied) but a property of the system where the individuals evolve (as long as the individuals satisfy a few special properties, namely variation and heredity, see below).
Here's the definition from Wikipedia:
At the most fundamental level, <PERSON> theory of evolution states that organisms evolve and adapt to their environment by an iterative process. This process can be conceived as an evolutionary algorithm that searches the space of possible forms (the fitness landscape) for the ones that are best adapted. The process has three components:
* variation of a given form or template. This is usually (but not necessarily) considered to be blind or random, and happens typically by mutation or recombination.
* selection of the fittest variants, i.e. those that are best suited to survive and reproduce in their given environment. The unfit variants are eliminated.
* heredity or retention, meaning that the features of the fit variants are retained and passed on, e.g. in offspring.
After those fit variants are retained, they can again undergo variation, either directly or in their offspring, starting a new round of the iteration. 1008
The overall mechanism is similar to the problem-solving procedures of trial-and-error or generate-and-test: evolution can be seen as searching for the best solution for the problem of how to survive and reproduce by generating new trials, testing how well they perform, eliminating the failures, and retaining the successes.
The generalization made in "universal" Darwinism is to replace "organism" by any recognizable pattern, phenomenon, or system. The first requirement is that the pattern can "survive" (maintain, be retained) long enough or "reproduce" (replicate, be copied) sufficiently frequently so as not to disappear immediately. This is the heredity component: the information in the pattern must be retained or passed on. The second requirement is that during survival and reproduction variation (small changes in the pattern) can occur. The final requirement is that there is a selective "preference" so that certain variants tend to survive or reproduce "better" than others. If these conditions are met, then, by the logic of natural selection, the pattern will evolve towards more adapted forms.
Examples of patterns that have been postulated to undergo variation and selection, and thus adaptation, are genes, ideas (memes), neurons and their connections, words, computer programs, firms, antibodies, institutions, quantum states and even whole universes.
Also, you may be interested by some terminology associated with this theory, for example for <PERSON> an individual that can evolve in an evolvable system is called a Unit of evolution[1]. This shows how much abstract and generalizable evolution can be.
[1]: <PERSON>, <PERSON>, Szathmáry E, Husbands P (2011) Evolvable Neuronal Paths: A Novel Basis for Information and Search in the Brain. PLoS ONE 6(8): e23534. doi: 10.1371/journal.pone.0023534 625