As a complement and supplement to the various articles in this issue devoted specifically to the manuscript olim Hiersemann 500/20, henceforth referred to as the “Syriac Galen Palimpsest”, or simply “SGP”, this article presents selected examples of how and why the undertext of SGP is important for scholarship, especially in disciplines beyond the confines of Syriac Christianity. Our examples are drawn from Sergius of Reš ʿAynā’s sixth century Syriac translation of Books VI-VIII of Galen of Pergamon’s important pharmacological treatise On simple drugs (hereafter “Simples”), which, as is well known, is found not only in SGP, but also and especially in another, older and better preserved manuscript, British Library Additional 14661 (hereafter “BL”). These selected examples illustrate two points (both of which require much further study in order to be elucidated fully): firstly, how the Greek text of Galen’s Simples, as published by Kühn, may in some cases be corrected on the basis of indirect textual evidence provided by Sergius’ Syriac translation, and secondly, how Sergius’ sixth century translation was to prove fundamental even centuries later, during the ʿAbbāsid translation movement centered in Baghdad.