This invention is often considered to have been the beginning of electronics, for this was the first vacuum tube.
An invention is considered to be inventive if it is not obvious in view of the prior art.
Every invention was considered impossible.
The Court therefore had to set a standard for when an invention would be considered complete enough to be "on sale".
An invention is considered to be new if it does not form part of the state of the art.
The invention of the revolving book case is considered to have happened earlier, and is credited to the layman Fu Xi in 544.
The effort on history says, "The best invention of the millennium is widely considered to be the printing press, which is obvious and right.
Although the invention of salad spinner is considered to be modern, earlier devices, including one from the 19th century, did exist and performed similar functions.
An invention which brings about a technical effect may be considered to be an invention.
In the early 1800's, patent applications could be rejected because the inventions were considered too complicated for laborers in Brazil's then overwhelmingly slave work force.