Scifi Concepts continued: Hardness

Hardness:
"Hard" science fiction is science fiction that assumes few, or even no, significant paradigm shifts in technology. A setting becomes softer with the existence of Faster than Light (FTL) travel or communication, teleportation, energy weapons, and other dramatic advances in technological capability that cannot be explained with current science.

"Hardness" and "softness" are measured on a sliding scale, with a setting becoming "softer" as it includes more extreme technologies. To assume that we will be able to build an engine that is capable of significantly higher speeds than is currently possible does not significantly soften a setting, but to assume we will be able to break the light barrier, or manipulate gravity, is. The presence of extraterrestrial life, fairly common anomalies which bend the laws of physics, and other setting detains for which there is currently no evidence, also make a setting softer.

A setting with no artificial gravity, where the earth has colonies on the moon and Mars, and engages in endeavors to mine the asteroid belt, would be a relatively hard science fiction setting. Comparatively, a setting focused on the movements of a spaceship across the galaxy as it solves moral and political dilemmas arising from interactions with alien societies would be a soft science fiction setting.

It is important to remember that these terms are not pejorative. Hard science fiction is not better than soft science fiction, only different. A reader who believes that the setting he is reading about is "hard" will likely be dismayed if "soft" elements make an appearance without significant explanation and purpose.