The Seat of Passions is Not in the Heart

33. The Seat of Passions is Not in the Heart

People think that the soul receives its passions in the heart.

In reality, the passions cause some alteration to be felt there.

This alteration is felt in the heart only through the mediation of a small [vagus] nerve that descends from the brain to the heart.

This is similar to how:

• pain is felt in the foot through the mediation of the nerves of the foot,
• stars are perceived in the sky through the mediation of their light and the optic nerves.

34. How the Soul and the Body Act on Each Other

The soul has its principal seat in the pineal gland.

From there, it radiates to the rest of the body through the:

• animal spirits
• nerves
• the blood

The blood carries all the impressions of the animal spirits through the arteries to all the members.

The small fibers of our nerves are distributed to the whole body.

Sensory objects excite movements in them by opening the pores of the brain in different ways.

• This causes the animal spirits contained in its cavities to enter into the muscles, moving the limbs various ways.

Other causes can move the spirits and guide them into the muscles.

The pineal gland is suspended between the cavities containing these spirits in a way that it can be moved by them in as many different ways as there are sensitive diversities in objects.

But it can also be moved by the soul.

The pineal gland receives as many impressions from the soul, that the soul has as many different perceptions as there are different movements in the pineal gland.

Whenever the pineal gland is moved by the soul or by any cause, the movement pushes the animal spirits surrounding the pineal gland towards the pores of the brain.

From those pores, they go through the nerves into the muscles, making them move the limbs.

35. How the Impressions of Objects Unite in the Pineal Gland

If we see an animal coming towards us, the light reflected from its body paints 2 images, one in each of our eyes.

These 2 images form 2 others, through the mediation of the optic nerves, on the inner surface of the brain facing its cavities.

From there, through the mediation of the spirits that fill these cavities, these images radiate towards the pineal gland.

This gland is surrounded by these spirits.

Each point [pixel] of this image goes towards the same point of the gland.

This creates that image in that gland.

Thus, the two images in the brain become one on the gland. This acts immediately on the soul to make it see the animal.

36. How Passions are Excited in the Soul

If this shape is very frightening and is similar with things that have previously been harmful, it excites fear in the soul.

This will then excite either courage or dread according to:

• the body’s temperament
• the soul’s strength
• whether one has previously defended oneself or fled from harmful things related to the present impression.

The spirits reflected from the image formed on the gland go from there:

• partly into the nerves that turn the back and move the legs to flee
• partly into the nerves that enlarge or constrict the orifices of the heart
  • This agitates the other parts that receive the blood, decompressing it a different way.

This blood sends spirits to the brain for maintaining fear.

• These keep those pores of the brain, that guide them into the same nerves, active.

As these spirits enter these brain-pores, they excite a movement in the pineal gland to make the soul feel this passion.

These pores relate primarily to the small nerves that tighten or enlarge the heart’s orifices.*

This makes the soul feel it primarily as being from the heart.