Peer review is the evaluation method that has characterized the scientific growth of the last four centuries, the first four of what is called modern science, indeed. It is matter of scientific communication inside scientific community, a subject too poorly studied in comparison with its critical importance for a scientific study of science (science of science). Peer review has been used for scientific paper evaluation before publication (editorial peer review) and for research proposal evaluation before financial support (grants peer review). Both cases present similar pros and cons, so I