Taking aliens for granted.

The idea of humanoid aliens is something that people all take for granted in science fiction. On any given episode of any television show, if you want that alien to speak or to be in any way sympathetic or threatening, it's always good for them to have mouths and arms and legs. Luckily, that's the way most of the actors come, with arms and mouths and legs. So, the aliens tend to be very humanoid.

If there is life, which I'm sure there is, somewhere in our galaxy, the odds that they have arms and legs and mouths and ears are probably quite remote. When it comes to space aliens in movies and in television series, people haven't really changed their idea of what they are. People expect a certain amount of believability that they never demanded before Star Wars and Steven Spielberg's various movies came out, because they used such remarkable visual effects.

Once the Star Trek movies evolved, the visual effects were wonderful, and when we started The Next Generation we had all of these visual effects that people had become used to. We were suddenly forced to try to do them on a television budget, and ended up notching up the expectations of state-of-the-art effects. But make-up, visual effects, what alien worlds look like, how aliens are dressed is constantly changing - people have become a little more sophisticated and want to see stuff that they find more believable.