The Sociological Ninety ten rules that are proposed in this paper, are based on the fundamental premise that various branches of social sciences like sociology, anthropology and economics are humancentric and are therefore inexact, and vary fundamentally from the more precise and exact sciences like physics, chemistry and mathematics which are characterized by precision and exactitude. A high degree of precision and certainty may not therefore manifest themselves in various branches of the social sciences, even if they at times make use of mathematical models or statistical techniques. Therefore, for every postulated rule in most fields in the social sciences, there are likely to be many different exceptions. These may be described as cultural variations and cultural exceptions, and exceptions over time or space. The name ‘Ninety ten’ is only an easy-to-understand and easy-to-use nomenclature. Real world exceptions to any given observation could be twenty per cent, five per cent, or take on any other value, but the above nomenclature is chosen for convenience. Variations across or within cultures or within or in between socio-cultural groups, socio-economic groups, occupational groups or any other parameter must be assessed based on the principles that we propose. This may be a basis for splitting up such groups if necessary for further study and evaluation, and the prerogative for this lies with the researcher. Thus, not only rule-based reasoning but also case-based reasoning must be used for various fields in the social sciences. Therefore, a fundamental premise of this paper is that exceptions must be sought actively, as these will lead to better research and hypothesis formulation. Thus, every researcher must think of rules and exceptions to those rules, and this must become a mindset. If exceptions are significant, they may warrant an altogether different line of research. This process will also greatly aid in inductive analysis, nomothetic rulebuilding and theorization, and play a major role in the ‘Globalization of science’, particularly social sciences.