Casting coins has been used for centuries as a way of consulting the I Ching and often favoured for its simplicity and ease. In contrast, the yarrow stalk method is widely considered more traditional, requiring dedication, time and careful elaboration of process. The coins may produce a result more quickly and directly (yang) while the yarrow stalks yield to time and can create contemplative focus (yin).
There are other significant methods which have not (yet) been implemented, in particular the “[[https://en.wikibooks.org/wiki/I_Ching/The_Ancient_Yarrow_Stalk_Method][Ancient]]“ (Neo-Confucian reconstruction) and “[[https://en.wikibooks.org/wiki/I_Ching/The_Modified_Yarrow_Stalk_Method][Modified]]” methods of casting yarrow stalks described by Huang and some of the more idiosyncratic variants that have appeared during the 20th Century CE.
Consulting the I Ching as an oracle, in its most simple form, involves asking a question, casting a hexagram and interpreting the hexagram along with any possible changes to the hexagram.
You can cast and insert a hexagram at the current point with ~i-ching-insert-hexagram~ or insert a specific hexagram as required with ~(i-ching-insert-hexagram 23)~
Sometimes the hexagrams may not display correctly or be too small to read. Ensure that you have a font installed that contains the hexagram characters (such as the [[https://dejavu-fonts.github.io/][DejaVu]] family or [[https://en.wikipedia.org/wiki/Apple_Symbols][Apple Symbols]] on macOS). The font and size can be adjusted as needed with minimal interference to how other characters are displayed….
If the glyphs don’t appear to change you may need to call ~(i-ching-update-fontsize)~
** changing or moving lines
The ~3-coins~ and ~yarrow-stalk~ methods calculate values for the lines of the hexagram (6 or 9) and changing lines (7 or 8) as described in the text and commentaries. These values are represented internally as binary pairs which are used to produce a single hexagram, or a hexagram and changing hexagram. The current package does not provide commentary for individual lines or changing lines, preferring the concise description of a hexagram (and potentially the changing hexagram).
The ~3-coins~ and ~yarrow-stalk~ methods produce slightly different probability distributions for casting a hexagram as detailed in the following table (and discussed in more detail in [[https://sabazius.oto-usa.org/probability-and-the-yi-jing/][Probability and the Yi Jing]])
In consulting an oracle the nature and source of chance, synchronicity or randomness can be considered important aspects of the process. Thus, this package can draw upon several source of randomness including =quantum= (sampling quantum fluctuations of the vacuum via [[https://qrng.anu.edu.au/][ANU]]), =atmospheric= (atmospheric noise via [[https://random.org][random.org]]), or =pseudo= (pseudo-random numbers provided by the local computing environment). Each method may be assessed for its suitability and set as necessary.
The =quantum= and =atmospheric= sources of randomness both use public APIs and can make hundred of calls (specifically 121, 125, 129 or 133 for the =yarrow-stalk= method) which can take seconds, or minutes depending on the service which may be rate limited. This can be used as a time for reflection. If you prefer to have a quicker casting, you can register an API key or use the local =pseudo= random source.
- A “True Random Number Service” https://www.random.org
- ANU QRNG Real time demonstration of high bitrate quantum random number generation with coherent laser light. Appl. Phys. Lett. 98, 231103 (2011) doi:10.1063/1.3597793
- [[https://www.gnu.org/software/libc/manual/html_node/Pseudo_002dRandom-Numbers.html][Pseudo-Random Numbers]] (The GNU C Library) and a description of [[https://www.mscs.dal.ca/~selinger/random/][The GLIBC random number generator]]
** The Noise of Heaven & Earth. Stochastic resonance.
The translation from Chinese into English by James Legge, /The Yî King/ (1882) as published in /Sacred Books of the East, vol. XVI. 2nd edition/ (1899) is in the public domain and available via [[https://archive.org/details/sacredbooksofchi16conf][archive.org]]. It appears to be the only significant English translation that is currently in the public domain. There is a parallel Chinese/English edition [[https://ctext.org/book-of-changes/yi-jing][《易經 - Yi Jing》]] hosted at the [[https://ctext.org][Chinese Text Project]] using the Legge translation.
The German translation and commentary by Richard Wilhelm, /I Ging Das Buch der Wandlungen/ (1924) is in the public domain and available via [[https://www.projekt-gutenberg.org/autoren/namen/wilhelm.html][Projekt Gutenberg]]. Wilhelm’s translation from Chinese into German was translated into English as /The I Ching or Book of Changes/ (1950) by Cary Baynes and should enter the public domain in 2047. Wilhelm’s translation has provided the basis for translation into several other European languages
A [[https://en.wikipedia.org/wiki/List_of_hexagrams_of_the_I_Ching][List of hexagrams of the I Ching]] and some details of the [[https://en.wikipedia.org/wiki/King_Wen_sequence][King Wen sequence]] can be found on Wikipedia.
[[http://jamesdekorne.com/GBCh/GBCh.htm][The Gnostic Book of Changes]] provides a guide for “Studies in Crypto-Teleological Solipsism” by combining several translations, notes and commentaries, yet exists in a copyright grey-area. There is another emacs lisp version of the i-ching that can be found on the [[https://www.emacswiki.org/emacs/i-ching.el][emacswiki]] which takes a slightly different approach and includes a few other methods, including calendrical, beads and the (unfortunately unimplemented) FUCKUP emulation mode as described in /The Illuminatus Trilogy/ (there is also [[https://github.com/Brianfit/I-Ching][a programmatic replication of the Yarrow Stalk Method of I-Ching Divination]] available in javascript.)
