Abstract
The present paper focuses on the concept of reasonableness, specifically in its legal understanding which, as a priority standard to be considerate in the contemporary law research, exhibits an important link with human reason and a philosophical concept par excellence. Reasonableness is generally perceived by the Author as opening the door to several legal considerations, especially those which regard the legislative techniques involving the law-making process according to the standards issued by the civil law tradition (a concept of law based on the fact that rules are the main core of law). By following the common opinion expressed by a number of legal philosophers who insist upon the importance of reasonableness in law, the Author points out legislators as those responsible for filling lacunae in existing positive law by explicit reference to reasonableness. The same assignment is addressed toward lawyers who are also able to applicate some criteria of reasonableness to societal values.