http://dswarmsikhttkg7jgsoyfiqpj3ighupfrvuz5ri3lu5q2dlqyrpgk7ad.onion/notes/frege-ancestral.html
And the general concept \(x\) is an ancestor of \(y\) in the R-series , namely the ancestral of the relation \(R\) — \(R^*\) — was first defined in Begriffsschrift ( BS (1879), §26, Proposition 76; BS (1884), §79) Consider \(a\) is an ancestor of \(b\), and \(b\) is an ancestor of \(c\) and so on, the series will be in the form of \(Rab, Rbc, Rcd, \dots\). Then Frege showed how to define the relation \(R^*\) (\(x\) is an ancestor of \(y\) in the \(R\)). 1.