The Validity of Scifi

How does one define the genre known as social science fiction? We use that term everyday in referring to different works of art, be it a movie or a piece of literature, but do we ever think about what science fiction, or scifi for short, means? Does scifi have to take place in the future? Does it have to involve aliens? Or does it just have to be something so radical, so unconceivable to the human mind that it is put in a separate category separate from the rest of the "normal" fiction literature?
I believe that scifi is an art form that has as its setting an alternate reality and technical progress as the ignition that starts the engine that drives the story. This definition stems from looking at the works we consider scifi. "The Time Machine" has an element of technical progress which fuels the story, allowing the protagonist to set off on his quest. Without the advanced technology in "Star Wars", there would be no intergalactic empire, no interplanetary travel, no story. Without technical progress as an element of the setting, even if it is only an implicit element, there can be no story.
The other element of the setting is the alternate reality. An alternate reality is a reality that differs from the reality that the author and his contemporaries live in because it takes place in the future, and as such is not something we can accurately describe, or the past or the present, and in this case relies on an advanced form of technology that we did not have in the past or now. This often entails a chain of past events that differs from the chain that produced our actual reality.
The elements of an alternate reality and technical progress seem to raise questions as to the validity of scifi as an artform. People criticize or do not take it seriously because the technical progress envisioned by the creator of the work seems implausible or even impossible. But is it impossible or are they just unable to conceive of such progress? The element of alternate reality also seems to result in criticism. Again, this seems to stem from an inability to conceive of a reality that differs from the one we live in. Is it invalid or wrong to think of a world that differs from the one we live in or do many people simply lack imagination and the courage to conceive of this world?
All too often, scifi is grouped with another genre, fantasy. Fantasy too, with the exception of "The Lord of the Rings", is looked upon with disdain. While fantasy has the element of magic or mysticism that is beyond man's control, scifi relies upon technology, something that is man-made and under man's control. Yet both art forms are too often relegated to the world of the dreamers, the outcasts, the introverts, not the realistic. Is it because they both take place in an alternate reality?
The question is 'What is so wrong in envisioning a world that differs from reality as we know it?' One of the main assumptions in economics, a social science, is that of perfect competition. But, in what world does perfect competition exist? In international relations, another social science, there exist the assumptions of the different paradigms of liberalism, mercantilism, and structuralism. None of these paradigms, however, accurately describe the world we live in. Rather, they present a perfect of an ideal world, an alternate reality because it differs from the reality we live in. But for some reason, social science receives respect both in academic circles and as a type of literature.
Critics of scifi need to not view the element of alternate reality as something that makes the events of a scif movie or novel implausible, but as an element that allows creators of scifi to present their theories of the world in the most fitting way they can. While praising the speculations of Samuel Huntington in his "Clash of Civilizations", a piece of literature that definitely stretches the truth of our reality, academics all too often ignore the many useful, sometimes more realistic theories that can be found in scifi. Although Orson Scott Card writes scifi novels, his theory about the presence of flood stories in all ancient civilizations that was presented in "Pastwatch" and his analyses of countries' not just characteristics, but personalities, found in the Bean series, have validity. They are solid theories that rely upon research and a thorough examination of the actual reality that we are faced with. Using the medium of scifi allows Card to make claims that might otherwise not be published because they're either viewed as radical or as offensive. Russia would no doubt be offended by its depiction in the Bean series and would deny possessing any of the characteristics ascribed to it, but this negative response does not mean that the analysis is correct. The alternate reality might seem like a concept difficult to grasp or as more often is the case, grasp, but that does not negate its validity.