manzia
Dowsing
Radiesthesia (from the Latin radius and the Greek aisthesis) is a practice that uses pendulums, rods or other instruments to detect supposed subtle "radiations" or "energies" emitted by objects, people, places or food. The term was coined in France in the twentieth century (radiesthésie); it is related to dowsing (searching for water with rods).
Tools
Pendulum: the most widespread. Y-shaped or L-shaped rods: used by dowsers to look for water or minerals. Specific dials to measure "vibrational rates". Standardised question charts ("which of these options?"). The French and German schools of the twentieth century (Mermet, Bovis, Lehr) codified complex systems.
Scientific status
Radiesthesia is classified as pseudoscience by academic science. Rigorous double-blind studies have shown results equivalent to chance. The ideomotor effect (involuntary hand movements amplified by the instrument) accounts well for the observed phenomena. It remains an exercise in concentration and symbolism, not a diagnostic system.
FAQ
Do dowsers really find water?
In rigorous tests they have not shown results above chance. When they "find" water, it is in zones where underground water is widespread.
Can I use it to choose between options?
As a personal intuition exercise it can be useful. As an objective diagnostic method, it is not.
Is it dangerous?
Physically no. In practice, avoid entrusting medical, dietary or financial decisions to it.