Controversial discussion and deviating views represent an integral part of science, which is often somewhat neglected for technical, psychological and political reasons. At Free Neuropathology we have implemented features so that authors and readers can take part in scientific discussion. We encourage the submission of “Opinion Pieces” which are in a separate category of papers in this journal. This is a channel for expressing personal but scientifically founded views on hypotheses, terminology, key papers, opinion making, politics or anything else related to neuropathology. In addition, and in order to stimulate discussion on papers published in Free Neuropathology, we use the open-source software Hypothesis which basically introduces an annotation layer over any paper. After signing-in and clicking the > arrow on the upper right side of the browser window, the Hypothesis side-bar will appear and you will be able to provide sentence-level comments, add critique, share information and engage in discussion.