The purpose of this article is to reflect and unveil the conceptions that exist around complexity, and the need to implement a complex thinking capable of examining knowledge in a non-partitioned, non-divided or reductionist way, recognizing in it a new way of thinking that dialogues with the real and that merges under an unfinished and incomplete knowledge. Therefore, the objective of this paper is mainly to discuss the paradigms and notions that exist around complex thinking and complexity sciences, for which some triggering questions will be discussed, which refer to what is complexity, what is the difference between complexity sciences and complex thinking, are these differences unrecognizable or not, and why, likewise, these questions are intended to demonstrate the point of view of some authors.