An internal state (S) of a man changes along with time (t) when psychological energy (P) works on him as expressed below using differentiation (d).
dS/dt = P*S
In this world, there are two types of decisive energy for a man: God (G) and Money (M).
dS/dt = (G+M)*S
If we could specify the mathematical functions showing G and M for each individual, we can see a mathematical function characterizing the internal state of each individual.
The modern physics is also based on the following equation that can offer a concrete mathematical form of a state of matter:
dF (t, x)/dt = H*F (t, x)
F: Function showing the state of an entity.
dF/dt: Change along time (t) of a state of an entity.
H: Total energy in a form, called Hamiltonian, that can mathematically operate on F as a double differentiation by space or distance (x).
This equation means that if you can define a mathematical expression of energy, namely H, you may get a mathematical expression of the state of an entity.
Here, surrounding energy comes first; the state of an object is a target.
It may be strange that a change along time can be equal to a change of a change in space. But, a wave is one of such natural phenomena, since its change of a change in time can be equal to a change of a change in space. (For example, acceleration is a change of a change in a distance a car runs per unit time.)
Check if you can perceive both the changes on a wave on the water surface.
(http://en.wikipedia.org/wiki/Wave_equation)
Anyway, it is rare to see an ugly wave on the water, but it is not rare to see an ugly internal state of a man on Wall Street, though it must be more complicated in the Vatican.
(Remember that a state changes along with time if energy works on it:
ds/dt = E x s)