If yes then doesn’t it contradict each stages of history being better than the other. Also what is the difference between ancient slave society/state and feudal society/state?
Depending on the time period, the average Roman citizen might have been a slave, because at times the slave population of the city outnumbered everyone else.
Two good vids by Paul Cockshott on these systems:
Again this depends on what you consider a Roman citizen, because slaves were not, they were treated as property.
YouTube links were detected in your comment. Here are links to the same videos on Invidious, which is a YouTube frontend that protects your privacy:
Link 1:
Link 2:
“Better” is a bit of a misnomer. What is actually claimed is that the “development of the productive forces” - which is to say, the extent to which that economic formation can get stuff done - increases at each stage.
In the model, before Rome (slave society) would have come primitive communism. The Romans got more architecture done, which is enough for the model.
Pushing on, the slaves got some of the benefits of the architecture. They were treated like property, but got use out of the aqueducts and hypocausts and roads that wouldn’t have existed otherwise.
How would you decide if their overall situation is “better”? It’s something British imperialists like to try to do for their empire, but I’d be wary of even trying the exercise, myself.
The Average Roman was either a beneficiary of a slave economy, or an active participant in expanding a vast slaving empire. What would be more important to look at is the life of the average person living in the empire, the vast majority of which were feudal style peasants and slaves being exploited in conquered lands and tributaries.