The biggest taboo in writing science fiction was the lack of realism. Science fiction usually explored topics such as science and technology, future society, and alien life in a fictional world. Therefore, it was necessary to maintain enough realism to prevent the fictional plot from being too different from the real world and causing readers to have unrealistic fantasies. Secondly, science fiction novels were also the most taboo to lack imagination. Science fiction usually showed the future of technology and human society through fictional worldviews and storylines. Therefore, the author needed to have enough imagination to create a shocking sci-fi world for the readers to feel the charm of the future. Lastly, the biggest taboo in writing science fiction was the lack of depth. Science fiction usually involved many scientific concepts and philosophical considerations, and the author needed to have enough depth and breadth to integrate them into the story and resonate with the readers.