The Third Force

Pythagoreanism is sometimes called 'number mysticism', and Pythagoras attached great importance to the numbers three and seven, and to the laws governing musical notes. Gurdjieff had also spoken of the "law of three" and the "law of seven". The law of three states that all creation involves a "third force". We are inclined to think in terms of dualities: positive and negative, male and female, good and evil.
Gurdjieff - who derived the ideas from the Sankhya philosophy of India - stated that, instead, we should try to think in terms of three. Positive and negative merely counterbalance one another, but if anything is to come of them, they must be given a push by a third force.