I Ching
The I Ching is the ancient art of inquiry through the tossing of coins. It can be traced back to its Asian roots and it is akin inquiring of an Oracle. Here questions are posed, coins are tossed and the combination of sides (heads or tails) point to an answer. The I Ching has been recommended by many spiritualists and there are many good books on the subject. A reference book is essential to read and understand and chart the combinations of sides called hexograms. The I Ching Workbook by R.L. Wing is an excellent resource.
