Cryptomnesia
Cryptomnesia is a phenomenon that occurs in the academic world where an author puts forward thoughts and ideas as being their own but that are actually inadvertent plagiarisms of work that had been read and absorbed in the past. Oftentimes this is the result of a person having read materials that have had such a deep effect on their own outlook and scholarship that they don't actually remember the source of those thoughts and ideas and don't recognize them as being borrowed rather than original. This is an important consideration in academics and other areas of publishing because of the very real problem of plagiarism which is the deliberate "theft" of intellectual property. For this reason journals and intellectual works are subjected to very strict editing and has led to the growth of computer software that can compare newly written materials to past bodies of work.