Science Fiction has always faced three problems from a critical standpoint: definition, history, and literary reputation. First, there is the two-part question of what is Science Fiction and how does it differ from Fantasy? As Frederick Andrew Lerner observes in his Modern Science Fiction and the American Literary Community, “the Science Fiction professionals themselves—writers, historians, and critics whose careers are closely associated with Science Fiction—have reached no consensus.” Perhaps the only definition that everyone can agree on is that given by Harry Harrison in his article “The Term Defined”: “The definition of science fiction is: Science fiction is.”

Science Fiction is often referred to as a form of Fantasy. Critic Julius Kagarlitski maintains in his essay “Realism and Fantasy” that “all fantasy is ‘scientific’ in the sense that it is engendered by that type of thinking whose mission it was to determine the real natural laws of the world and to transform it.” Kagarlitski also notes that “the history of fantasy is a very long one,” unlike Science Fiction, which most critics agree has only been around for the last couple of centuries.

The problem of defining Science Fiction’s history is steeped in controversy. Although some critics and historians claim that writings several hundreds of years old are Science Fiction, the leading argument—and the one that has seen the most acceptance—was offered by British Science Fiction author Brian Aldiss. In his book on the history of Science Fiction, Trillion Year Spree, Aldiss maintains that Shelley’s Frankenstein is the first true Science Fiction work due to its reliance on scientific methods. “Frankenstein’s ambitions bear fruit only when he throws away his old reference books from a pre-scientific age and gets down to some research in the laboratory,” says Aldiss.

The arguments of definition and history are often laid aside, however, when it comes to discussing the literary merits of Science Fiction and Fantasy. Although some very notable authors like Wells and Verne wrote critically acclaimed Science Fiction works, it has taken a while for Science Fiction and Fantasy works to gain acceptance in the mainstream. This is due in large part to Gernsback and his publication of Science Fiction and Fantasy pulp magazines. The same magazines that helped increase popular readership in the field, also served to distance critics.

It has been through the works of specific writers like Bradbury and Vonnegut that the genre has been able to transcend its pulp image and garner the positive attention of critics. Works like The Martian Chronicles and particularly Slaughterhouse Five have also found favor with academia and are often taught in the classroom. Jack Williamson noted this trend in his 1974 article “SF in the Classroom”: “From a standing start only a dozen years ago, Science Fiction has now become a popular and reasonably respectable academic subject.”

This trend continues today. As for the mainstream critics, they tend to favor the types of stories they always have: the ones that transcend the genre of Science Fiction and illustrate more universal themes of humanity.