It's beginning to look like #Plato was more prescient about governments than Karl Marx ever was. After all, Plato claimed that democracy eventually degenerates into oligarchy before finally reaching a tyrannical state. OTOH, #Marx argued that capitalism emerged from feudalism only to suffer crises until it finally reaches an utopian ideal in communism. Given the recent events in USA & the rise of oligarchs, #latestage #capitalism has become #neofeudalism, Plato wins this round.
Plato's argument of government decline (Republic): societies pass through a predictable cycle of government forms, each degenerating into the next: #aristocracy (rule by the wise), #timocracy (rule by honorable), #democracy (rule by the people), #oligarchy (rule by the rich), and #tyranny (rule by dictator). Plato specifically claimed that democracy's emphasis on freedom & equality leads to disorder, making it ripe for a tyrant to seize power under the guise of restoring order.
Marx's theory of historical materialism asserts that the material conditions of a society's mode of production shapes its social structure & political #superstructure.
Human history is a series of class struggle. Marx predicted that capitalism due to conflicts btw the #bourgeoisie & the #proletariat leads to its eventual demise, a proletarian #revolution overthrowing capitalism & resulting in a socialist state, in transition towards a #stateless & #classless society: communism.
Now the question is whether Marx's analysis of capitalism's crises & potential of revolutionary change remains possible, esp given economic inequality, labor exploitation & sustainability of capitalist growth.
A neo-feudalist system, one with extreme economic inequality & concentration of power, do reflect concerns about the direction of capitalist societies, tho it may not align with Marx's original predictions.
Then again any application of philosophical theories to modern events is always subject to interpretation. Plato's cycle of government forms is about the fragility of democracy & potential for decline into tyranny whereas Marx's focus on class struggle is a critique of capitalism. 
@Gotterdammerung Polybius’ theory on anacyclosis covers the idea that it cycles.

@mattjohns Thank you for mentioning Polybius' theory of political cycles.

Polybius, a Hellenistic historian, outlined a cycle of government forms (anacyclosis) where regimes pass through the inevitable stages: monarchy to tyranny, to aristocracy, to oligarchy, to democracy, & finally to ochlocracy before returning to monarchy. But I like Machiavelli's more pragmatic & less cyclical version of governance. Instead of the inevitable cyclical change, Machiavelli focused on the dynamics of power.

@mattjohns In the Discourses, Machiavelli points out the advantages/disadvantages of each form of government (monarchy, aristocracy & democracy). He proposes that a mixed government with elements of all three will be the most stable & enduring. Then again, this does echo Polybius' claim that the Roman Republic was stable & successful because it combined all three elements. 
@Gotterdammerung Funny, I just finished the #Republic and when I read about the decline of democracy into tyranny, I had exactly the same impression. It feels like a comment on recent events. I quickly checked (just to be really sure) but yes, the guy is 2500 years dead and its still spot on. Spooky.