Hope gives place to its opposite despair, joy to sorrow, and regret succeeds expectation.

No one can enumerate the actual phases of the emotional life.

The differences which are most pronounced--as between hope and fear, joy and sorrow, anger and love--have special names, and their stimulating causes are so constant that they have also certain fixed ways of showing themselves in the body, the so-called emotional Expressions.

It is by these that we see and sympathize with the emotional states of other persons.

The most that we have room here to say is that there is a constant ebb and flow, and that we rarely attain a state of relative freedom from the influence of emotion.
The fixed bodily Expressions of emotion are largely hereditary and common to man and the animals.