Many of you inquired about incorporating step-relations and in-laws into the solution to Lichtenberg's riddle. Lichtenberg himself proposed such a scenario as a preliminary solution to the riddle in The Waste Books (translated by R. J. Hollingdale). This excerpt has been annotated by Winkelman, whose comments appear in brackets (please excuse my horrendous penmanship in the diagram below; I am writing this from a frigid campsite in northern California, and I forgot my gloves):


Two old men [M1, M2] each of whom has a grown-up son [M3, M4] each of whom has an unmarried daughter [F1, F2] marry two young girls who are sisters [F3, F4]. After the wedding, however, the two old men are ill and die before the marriages are consummated. After their deaths the two young men marry their stepmothers: these six last [shaded boxes] are those who lie buried here. For here two sisters are also lying with their two brothers[-in-law], because every woman calls her sister's husband her brother.


"Not only is there a fudge-factor with the stipulated 'brothers' actually panning out as brothers-in-law," writes Winkelman, but Lichtenberg's preliminary solution requires that daughters, mothers, and grandmothers be regarded as step-relations. "The correct solution," he notes, and as we see in Edward's solution above, "does not require these feints."

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