Some reasons are to teach the viewer or to create a emotional response. Also the artist made mosaics to express their faith through their art. And medieval christian arts purpose was to convey religious meaning in a dramatic fashion, one example would be statues they built for ritual purposes.
U.S Democracy is a Republican Democracy where the EVERY CITZEN is allowed to vote. in Ancient Greece, they have a Direct Democracy where ONLY adult males where permitted to vote, and the people where allowed to make desicions for bills and laws where in the US that is not allowed.
