Paraphrased from a speech I gave to my debate team.
Throughout human history, there are many conflicts that we experience throughout life as an individual and socially. Currently, one issue I am experiencing is an unofficial long-distance relationship. 4000 KM seems like the other end of the Universe to me, and it happens to many people throughout their lives. What if the relationship is across a galaxy? In terms of Dune there are times when Jessica is a long distance from her husband Leto. It makes the pitiful 4000 KM seem short, even though it isn't. It allows authors and philosophers to put issues in our personal lives into a format that is understandable regardless of race, sex, or creed. A major part of the crusade for Civil Rights was when Captain Kirk and Ahura had a very informal relationship. Not to mention Spock's father, a Vulcan, and his mother, a Human. This is a format that probably persuaded some people who were indifferent then had to side with the civil rights movement.
Other issues include the origins of religion. In Dune we see the creation of an entire religion with all the complexities. By the third book Muad'Dib has already taken on supernatural aspects of things that did not happen yet the Fremen believed it with all their hearts. To have such a comparison in a modernistic setting would either look and read as a very silly book that people would be offended by. By putting his insight into a format that would reach across faiths, Frank Herbert created what I consider to be the greatest book that is accessible to people from all ethnicities and faiths. Philosophy is included in this topic too, giving the
Litany Against Fear which is influential to all fans of Dune.
On the Scientific level Science Fiction has it's most obvious gift to society. In Arthur C. Clarke's writing he explains the scientific principles behind his ideas having video calls and walking on the moon in his most famous work, 2001. In his work
Rendezvous with Rama he has a gigantic spaceship the size of a small planet come into the Solar System on it's long journey. This concept was little explored and was given in great scientific detail. In I, Robot by Isaac Asimov we see the original example of robots gone evil, a concept that has been used in countless stories after then.
To sum it up cleanly, putting raw human emotions and political controversies in a format accessible to many people. By doing this, science fiction authors are able to delve into a topic with a freedom not available to many other genres that truly makes it a wondrous tool for explaining answers to that question of humanity.