Ibn al-Nafis

The blood is purified in the right ventricle, then it is carried to the left ventricle where the spirit is generated, and from there it is distributed to the body.

The heart has only two ventricles, and there is no visible passage between them.

The blood, after it has been refined in the right ventricle, must be transmitted to the left ventricle where the vital spirit is generated. But there is no open passage between these two ventricles, for the septum between them is thick and there are no visible pores as some have imagined. Therefore, the blood must pass from the right ventricle through the pulmonary artery to the lungs, spread through their substance, be mingled with air, and then pass through the pulmonary vein to the left ventricle.

The lungs are necessary for the completion of the blood's journey and for its aeration.

The pulmonary artery carries blood from the right ventricle to the lungs, and the pulmonary vein carries it back to the left ventricle.

The vital spirit is generated in the left ventricle from the refined blood and air.

The heart is the source of life, and its proper functioning is essential for the health of the entire body.

Observation and experimentation are the foundations of true knowledge.

Do not accept anything without proof and careful examination.

The human body is a marvel of creation, and its intricacies reveal the wisdom of the Creator.

The purpose of medicine is to preserve health and to cure disease.

Anatomy is the key to understanding the functions of the body.

The arteries carry blood from the heart to the body, and the veins carry it back to the heart.

The liver is the organ responsible for producing blood.

The brain is the seat of the intellect and the senses.

The nerves transmit sensations and commands throughout the body.

The muscles are responsible for movement.

The bones provide support and protection to the body.

The skin is the protective covering of the body.

The digestive system processes food and extracts nutrients.