I'm a bit of a Spenglerian on this matter. His civilization model seems to make sense to me. We are in the winter, a decline of sorts. His description is as follows -
(I shamelessly nicked this from wikipedia)
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Spring: Intuition, powerful cultural creation from awakening souls, unity and abundance.
* Religion: Birth of a grand myth signifying a new conception of God. Fear and longing for the world. Earliest metaphysical organization of the world. High scholasticism.
* Art: Religious art considered as an integrated part of religious devotion. Gothic cathedrals, Doric temples. Development of Ornamental art as against the persistent, ahistorical type of Imitative art.
* Politics: Feudalism, warrior aristocracies. Division between two primary Estates: Nobility, which is the estate proper, contains within itself the highest aspirations of its race and is therefore symbolic of the particular people in question, as well as being representative of Time in the sense of Directedness and Destiny; and Priesthood, which is the anti-Estate, pursuing eternal Truth and attempting to subordinate Blood to Intellect primarily through asceticism, but also through scholasticism.
Summer: Maturing consciousness. Earliest urban-civil society and critical thought.
* Religion: Reformation: revolt of the religious moderates against the early religion. Beginnings of a purely philosophical movement. Contrasting idealistic and realistic systems. Mathematical breakthroughs leading to a new conception of the world. Rationalism. The depletion of mysticism from religion.
* Art: Development of high artistic traditions. Both artistic medium and style express the fundamental nature of the soul of the culture. Struggle between different artistic mediums, representing the culture's striving to discover its proper mode of self-representation.
* Politics: Absolutist states. Conflicts between aristocracy and monarchy. The political centre shifts from castles and estates to the cities.
Autumn: Urban rise. High point of disciplined organizational strength.
* Religion: Faith in the omnipotence of rationality. Cult of Nature. The height of mathematical thought. The last idealists. Theories of knowledge and logic.
* Art: Fulfillment of high artistic potentials of culture- sculpture in Greece, contrapuntal music in the West. At the beginning of Autumn, art possesses complete freedom to manifest the Destiny-vision of a people through its particular perfected formal technique. However, the end of Autumn witnesses the exhaustion of the possibilities of that technique, leading to craft-art in imitation of the great style as well as artistic revolt.
* Politics: Struggles between the aristocracy and the bourgeoisie. Revolutions. Napoleonism.
Winter: Coming fissure in the world-urban civilization. Exhaustion of mental organization strength. Irreligiousness rises.
* Religion: Materialism: Cults of science, utility, and luck. Ethical-social ideals: philosophy without mathematics, skepticism. The last mathematical thinkers. Decline of abstract thinkers, and the rise of specialized academic philosophy. Spread of the last ideas.
* Art: End of symbolic art. All art becomes meaningless subjects of fashion.
* Politics: Democracy, the rule of the rich, followed by caesarism and bureaucracy.
The Decline of the West. Good book.