Quoting from the article:

Thurner and co found that positive behaviour intensifies after an individual receives a positive action.

"The probability of acting out negative actions is about 10 times higher if a person received a negative action at the previous timestep than if she received a positive action," they say.

"We interpret these findings as empirical evidence for self organization towards reciprocal, good conduct within a human society," they say.

In other words, humanity is fundamentally good.