What part is in charge of automatic processes?

In science, Gibbs free energy can tell if a chemical reaction is spontaneous. It is given by the formula:

G = H - TS

H = enthalpy of reaction

S = entropy of reaction

T = temperature in Kelvin

If G is negative the reaction is spontaneous.

However if activation energy is high, reaction rate is slow and the reaction may take a while to progress, regardless of its spontaneity.