Logical fallacy/Lack of imagination

An argument by lack of imagination is the logical fallacy that states because something is currently unexplicable, that it did not happen, or that because one cannot conceive of something, it cannot exist. It is used often to attempt to invalidate a scientific theory by pointing out a phenonmenon which the theory does not readily explain. This is rather simple to do because there are a lot of phenonmena that are currently unexplained. However, the mistake is to assert that because a phenonmenon is unexplained, that it is unexplainable.

Another example of this argument is Ayn Rand's defense of patents and copyrights. She argued that such laws were "obviously necessary" for authors and inventors to earn a living (or in other words, that she could not imagine any ways for them to earn a living without them, so such methods can't exist), so they should be supported.