It explicitly requires that there must be time limits. That isn't required if all you want to do is reward innovation. The time limits are required because the ultimate purpose is to enrich everyone, which means that everyone gets access once the inventor has gotten a fair shake. For patents in particular, it is well-established in the law (though poorly followed in practice) that a patent ought to serve as a guide to replicating the invention, with the inventor being assured that no one can do so without his permission until the patent expired.

Unfortunately the time limits are useless if they are allowed to grow them indefinitely. In the US, the copyright length has extended from 14 years (with another renewal for 14 years) to life + 70 years. There's nothing fair in Life + 70 years.

On patents - they were meant to replace the need for trade secrets, unfortunately most patents that pass these days is for things that can be replicated without looking at the patent's application. And while I understand somewhat the need for patents in the health-care industry (only to a certain extent, since on the other hand access to quality health-care should be a basic right), the situation we are in is completely ridiculous.

In the end, the inventor already benefits by being first to market and a patent is only morally justified if the research costs were too big, allowing the inventor to recover those costs in the face of potential competition that may replicate the results and for which those costs weren't an issue. On the other hand, if patents would disappear tomorrow, I'm pretty sure that people would still go on, building and inventing things. So the benefit to society at large is questionable.

The intent was to incentivise /publishing/ of inventions/mechanisms rather than keeping them a secret. Thus allowing others to build on top of that knowledge.

One way to incentivise this is to grant a /temporary/ monopoly, and require people to publish in exchange. When the temporary monopoly expires everyone else can fully benefit from the invention.

> What makes you say that this was the "original intent" of patents?

The original meaning of the word "patent" might be a bit of a clue here.

The problem that patents tried to solve was of people keeping their innovations secret (in order to maintain an edge on their competitors), and that when they died their secrets died with them. Encouraging people to make public work they were doing anyway way, in the first instance, the way the patent system promoted progress.