History is often viewed in terms of current social standards. Of course this isn't accurate.

PreVictorian: Take the concept of "survival of the fittest" out of your vocabulary. The common person thought that prayer and clean living were the main elements of success.

Prerennaissance: Do the above, then take your dictionary and rip it up. Then try to use it for basic communication.

Premedieval: Do the above, then realise that you are a Noble or powerful priest. Your serfs have the intellectual development of your cat.

Iron Age: There is virtually no intellectual community. Most concious thought is oriented toward warfare, which is a viable alternative to harvesting.

Bronze Age: Scientific Method invented! Technological remains largely a matter of luck. The intellectual community primarily pursues philosophy, language and math.

Stone Age and before: Technological advance is extremely slow, probably due to limitations of population density, longevity, trade routes and communication skills, as well as intellectual tools.