"Alpha waves in the human brain are between 6 and 8 hertz. The wave frequency of the human cavity resonates between 6 and 8 hertz. All biological systems operate in the same frequency range. The human brain's alpha waves function in this range and the electrical resonance of the earth is between 6 and 8 hertz. Thus, our entire biological system - the brain and the earth itself - work on the same frequencies. If we can control that resonate system electronically, we can directly control the entire mental system of humankind."
NIKOLA TESLA