The philosophical literature today is moving off in two divergent directions. Both share the goal of understanding the foundational facts underlying the knowledge process and which can only be experienced individually; but while one direction strives to illuminate and clarify these facts by breaking down the terms in which the facts are expressed, it suits the needs of the other to obscure them. The latter, of course, is always possible since the words, which surround the facts like a mushy porridge, are difficult to control and in their emptiness are often completely irrefutable. It should therefore be stated from the start that Schlick's representation belongs to the first direction, and this must be considered its initial virtue in a time of increasing philosophical unrefinement (including among the tenured philosophers).

Its second merit is that it bases its critique upon a systematic construction including a closed framework of concepts, and does not at all shy away from manipulating and shaping them until they are integrated into this framework. This is an act deserving of thanks because it creates a work of thought that gives rise to discussions whose cognitive value can be clearly assessed. In addition, the language used is pleasingly sober, completely excluding all affected attitudes and not confusing ethical sentiment with epistemological clarification.

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