Metaphysics about two thumbs being cut off in three days is unscientific and unbelievable. The following is an auspicious and unlucky statement about cutting your finger:
Significance of finger cutting in geomantic numerology. In the traditional culture of China, the finger is one of the important body parts, and it is also the concentrated place of human acupuncture points. Therefore, cutting your fingers is considered a good sign.
A lucky way to cut your finger. In Sichuan and other places, finger cutting is considered as the way to seek money, because seeing blood can turn evil into disaster and bless yourself to make a living smoothly.