> Granting the inventor a monopoly costs more to society than it benefits the inventor himself. You cannot make that assertion without empirical evidence. You

> Granting the inventor a monopoly costs more to society than it benefits the inventor himself. You cannot make that assertion without empirical evidence. You bring up good points about the costs of patents, but note that your language ("can", "could") is all in terms of potential. The studies I've read consider all those points and then try to quantify them, even going as far as seeing how they play out in different industries. Other studies raise points which show the benefits of patent systems (increased R&D spending, increased diversity in the areas of innovation, increased probability of securing VC funding) and quantify those too. Other studies actually find counter-intuitive results about monopolies in general (e.g. monopolies can be more innovative than startups by some metrics -- think Bell Labs, Xerox, MS Research -- which casts doubt on the "monopolist gets lazy" argument). There are tons of studies presenting interesting results, and of course, there are studies that point out flaws in these. The problem is, it is impossible to compare these results quantitatively because the data, methods, assumptions, interpretations, shortcomings and metrics are wide, varied and often orthogonal. How can you meaningfully compare a lower rate of stitch / minute improvements (that was used as a proxy for the cost of sewing machine patents) with the increased diversity of industries participating in a technical convention (which was used as a proxy to measure the beneficial effects of introducing a patent system)? And to top it off, both studies were by the same author (Petra Moser)! This is just one example -- there are as many metrics as there are academics researching this area.