This text examines the method of conceptual thinking that involves pushing specific functions or properties to their extremes to create mental models. This ability to construct models based on incomplete sensory data is a fundamental achievement of human reason. The author illustrates this process using the example of ancient Greek atomism, where philosophers chose between infinite divisibility and the existence of indivisible particles (atoms). Although this is a purely mental operation lacking direct sensory verification, it plays a crucial role in the history of philosophy and science. The article further traces the evolution of these ideas from Aristotle and Leibniz to modern quantum physics, which applies the concept of indivisibility to energy quanta and potentially to space and time. The paper concludes that the construction of mental models through conceptually structured thinking is a necessary prerequisite and an organic part of scientific work, enabling the investigation of limit situations and the boundaries of reality.