Take a pack of (78) Tarot playing cards. Shuffle; cut. Draw one card. Without looking at it, try and name it. Write down the card you name, and the actual card. Repeat, and tabulate results.
This experiment is probably easier with an old genuine pack of Tarot cards, preferably a pack used for divination by some one who really understood the matter.
Remember that one should expect to name the right card once in 78 times. Also be careful to exclude all possibilities of obtaining the knowledge through the ordinary senses of sight and touch, or even smell.
There was once a man whose fingertips were so sensitive that he could feel the shape and position of the pips, and so judge the card correctly.
It is better to try first, the easier form of the experiment, by guessing only the suit.
Remember that in 78 experiments you should obtain 22 trumps and 14 of each other suit; so that without any clairvoyance at all, you can guess right twice in 7 times (roughly) by calling trumps each time.
Note that some cards are harmonious.
Thus it would not be a bad error to call the five of Swords ("The Lord of Defeat") instead of the ten of Swords ("The Lord of Ruin"). But to call the Lord of Love (2 Cups) for the Lord of Strife (5 Wands) would show that you were getting nothing right.
Similarly, a card ruled by Mars would be harmonious with a 5, a card of Gemini with "The Lovers".
These harmonies must be thoroughly learnt, according to the numerous tables given in 777.
As you progress, you will find that you are able to distinguish the suit correctly three times in four, and that very few indeed inharmonious errors occur, while in 78 experiments you are able to name the card aright as many as 15 or 20 times.
When you have reached this stage, you may be admitted for examination; and in the event of your passing you will be given more complex and difficult exercises.