Equilibrium

When an individual encounters a crowd, a curious thing happens. The crowd is changed by the individual, and the individual is changed by the crowd. The change may be imperceptible. But in both cases, the impact is felt.

With zero people on earth, it is filled with everything except the person. 

With one person on earth, the mind is formed.

With two people on earth, the bond is formed.

With three people on earth, the tension is formed.

With four people on earth, the equilibrium is formed.