The Status of the Quadrivium in the Corpus on Logic of the Brethren of Purity (Iḫwān aṣ-Ṣafā’)

Crina Galita



This article proposes some reflections on the status of the quadrivium in the epistles X–XIV of one of the best known encyclopaedia of the Brethren of Purity Rasā’il, by reconstructing the implied methodology of how the quadrivium is applied within a theoretic philosophy and therefore how all these aspects concur in order to obtain demonstrations that are in complete cohesion with soundness. Following a hermeneutical methodology, this research explores the ways to get to the universal truth and how exactly one arrives to it. The first part explains what perceived science is and what its defining features are, while the second part illustrates a distribution of the application of the quadrivium in relation with what the Brethren of Purity established as methods of acquiring knowledge. Finally, the last part evaluates some examples that can be traced from a ground of the quadrivial disciplines in order to show how some elements of formal logic are evaluated.


quadrivium; science; ’IIIḫwān aṣ-Ṣafā’ (Brethren of Purity); logic; knowledge

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