The image is drawn for illustration of an argumentation in a talk page debate. The factual correctness of the image can be disputed, see the later development of the thread . The (maybe obsolete) argumentation for which the image has been drawn was the following below:
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{{Information |Description=Comparison between Hilbert-styledeductionsystem and natural deduction, approached with the concept of judgment |Source=self-made |Date=6 Jan 2008 |Author= Physis |Permission= |other_versions= }}