Transparent Intensional Logic (TIL) explicates objective abstract procedures as so-called constructions. Constructions that do not contain free variables and are in a well-defined sense ‘normalized’ are called concepts in TIL. An argument is given for the claim that every concept defines a problem. The paper treats just mathematical concepts, and so mathematical problems, and tries to show that this view makes it possible to take into account some links between conceptual systems and the ways how to replace a non-effective formulation of a problem by an effective one. To show this in concreto a well-known Kleeneś idea from his (1952) is exemplified and explained in terms of conceptual systems so that a threatening paradox is avoided.