the work tries to approach the following problem: is it possible to affirm in the social sphere the existence of real entities or regularities of "independent" subsistence, previous to any theoretical model who should try to represent them? the aim of this investigation is to apply the concept of ‘ realism brings over of entities ‘, proposed by hacking, to the area of the social sciences, in order to explain which is the nature of the theoretical entities that are in the habit of postulating the sociological theories, and if at least some of them it survives in different theoretical approaches (even in opposite or incompatible theories), in a such way that we might think that they possess certain type of existence per-se, that is to say, previous and independently from any cognitive human approximation. if such out the case, it is necessary to ask then in what sense we can postulate the real existence of the above mentioned "entities". to answer this question i will propose a possible classification of the diverse significances (meanings) that can acquire the term(end) "reality" in the area of the social facts. i will take the metaphor popperiana from the ‘ three worlds ‘ to the ends (purposes) of applying it partially to three possible senses of reality: the first one referred to those laws and natural circumstances (previous and independent from any human intervention) that would make possible to - priori the existence of the social world. the second one linked to the reality of the mental conditions (states), and third related to the cultural resultant products of the physical and mental intervention of the human being on the nature, which once expressed would acquire an own(proper) gravitation that in turn would exercise a feedback on the natural environment (world 1) and on the individual consciences (world 2).