The external signs of these Passions

112. What are the external signs of these Passions?

What I have put here makes the cause of the differences in the pulse and all the other properties I have attributed to these passions above quite clear, without needing to explain them further.

But because I have only noted in each what can be observed when it is alone, and which helps to understand the movements of blood and spirits that produce them,

I still need to address several external signs that usually accompany them and that are better noticed when they are mixed together, as they often are, than when they are separate.

The main signs are the actions of the eyes and face, changes in color, tremors, languor, fainting, laughter, tears, groans, and sighs.

113. Actions of the Eyes and Face

The action of the eyes reveal all passions.

Even the dullest servants can tell by their master’s eyes whether he is angry with them or not.

Yet, although these actions of the eyes are easily noticed and understood, describing them is not easy because each is composed of numerous subtle changes in the eye’s movement and shape.

These changes are so specific and minute that each one cannot be observed separately, even though the overall effect of their combination is quite noticeable.

The same is true for the actions of the face that accompany passions.

These are more prominent than those of the eyes. But they are also difficult to distinguish.

Their differences are so slight that some people make almost the same expression when crying as others do when laughing.

Some facial expressions are quite distinctive, such as:

• the furrowing of the brow in anger
• certain movements of the nose and lips in indignation or mockery

But these are more voluntary than natural.

In general, all actions of both the face and the eyes can be altered by the soul, which, when trying to conceal its passion, strongly imagines an opposing one.

As a result, these expressions can serve as well to mask one’s emotions as to reveal them.

114. Changes in Color

It is not as easy to prevent oneself from blushing or turning pale when some passion causes it, because these changes do not depend on the nerves and muscles, as do the previous expressions.

Instead, they come more directly from the heart which is the source of passions.

The heart prepares the blood and spirits that produce the passions.

The color of the face comes only from the blood, which continuously flows from the heart through the arteries into all the veins, and from the veins back to the heart.

This colors the face more or less depending on how much it fills the small veins near the surface.

115. How Joy Causes Blushing

Thus, joy makes the complexion more vivid and rosy because it opens the heart’s “sluices”. This causes the blood to flow more rapidly through all the veins.

As it becomes warmer and more refined, the blood slightly swells all the parts of the face, giving it a more cheerful and radiant appearance.