Breakdown of Согласно этой теории, общество развивается по-другому.
этот
this [f: эта, n: это]
по-другому
differently (in another way)
теория
theory
общество
society
Questions & Answers about Согласно этой теории, общество развивается по-другому.
Why are the words этой теории in this specific case?
The preposition согласно (according to) strictly requires the Dative case. The Nominative phrase эта теория (this theory) becomes этой теории in the Dative.
Wait, этой теории looks like the Genitive or Prepositional case too. How can we be sure it is Dative here?
You are right to notice that! For feminine nouns ending in -ия (like теория) and the pronoun эта, the Genitive, Dative, and Prepositional cases share the exact same form: этой теории. We only know it is Dative here because of the grammatical rule that the preposition согласно governs the Dative case.
Why does по-другому have a hyphen, and how is it formed?
This is an adverb meaning "differently" or "in another way". In Russian, you can turn many adjectives into adverbs meaning "in a [adjective] way" by adding the prefix по- and changing the ending to -ому or -ему. Here, the adjective другой (other/different) becomes по-другому. By rule, these specific adverbs are always hyphenated.
Why use the reflexive verb развивается instead of just развивает?
The non-reflexive развивать means "to develop" in a transitive sense, where a subject develops a direct object (like developing a business or a skill). In this sentence, society isn't developing something else; it is undergoing development itself. Adding the reflexive -ся ending makes the action intransitive.