τετρακτύς: Difference between revisions

|Definition=ύος, ἡ, (τετράς) Pythagorean name for <span class="sense"><p>&nbsp;&nbsp;&nbsp;<span class="bld">A</span> <b class="b2">the sum of the first four numbers</b>, i.e. <span class="bibl">10</span> (= <span class="bibl">1</span>+<span class="bibl">2</span>+<span class="bibl">3</span>+<span class="bibl">4</span>), ναὶ μὰ τὸν ἁμετέρᾳ ψυχᾷ παραδόντα τετρακτύν, παγὰν ἀενάου φύσεως <span class="title">Carm.Aur.</span>48, cf. <span class="bibl">S.E.<span class="title">M.</span> 7.94</span>, TheoSm.<span class="bibl">p.94</span> H., <span class="bibl">Hierocl.<span class="title">in CA</span>20p.465M.</span> </span><span class="sense">&nbsp;&nbsp;&nbsp;<span class="bld">II</span> <b class="b2">the four terms</b> (<span class="bibl">6</span>:<span class="bibl">8</span>:<span class="bibl">9</span>:<span class="bibl">10</span>) <b class="b2">of the proportion corresponding to the chief musical intervals</b>, <span class="bibl">Nicom.<span class="title">Exc.</span>7</span>, <span class="bibl">10</span>; also <b class="b2">their sum</b> +<span class="bibl">1</span> (= <span class="bibl">36</span>), ibid.; <b class="b2">the sum of the first</b> <span class="bibl">8</span> <b class="b2">numbers</b>, Plu.2.381f.</span>