Islam gives seventeen a wholly positive and highly practical role: the five daily obligatory prayers contain seventeen units, rakahs, in total, two at dawn, four at midday, four in the afternoon, three at sunset and four at night. Every observant Muslim performs seventeen rakahs of fard prayer each day, so the number is woven into the basic rhythm of religious life. Elsewhere seventeen is the syllable count of the Japanese haiku, arranged five-seven-five, and it appears in scattered devotional lists, but nothing rivals the prayer cycle for making it a lived number. The contrast is striking: a number treated with suspicion in the classical Mediterranean is, in Islam, the daily measure of devotion.
Balliett's 1908 chart reduces seventeen to eight, material capability and authority in the standard modern keyword list, a root shared with twenty-six and thirty-five; none of Balliett, Cheiro, Florence Campbell or Juno Jordan record any awareness of the older Roman or Pythagorean unease over seventeen described above, and Walter Burkert's study of the Pythagorean tradition would treat the coincidence, an American chart independently landing on a number the classical Mediterranean also distrusted, as exactly that, a coincidence rather than a shared inheritance.