I T IS clear that these opinions are so contradictory and irreconcilability that all are doubtful. T he blood is supposed to ooze through tiny pores in the septum of the heart. From these and many other considerations it is clear that what has so for been said on the movement and function of the heart and arteries must seem obscure, inconsistent, or impossible to the thoughtful student. It will therefore be proper to investigate the matter more closely, to study the movement of the heart and arteries not only in man but in all animals possessing a heart, and to search out and find the truth by frequent experiments in living animals, and by constant observation. The heart is a muscle.
All muscles act in contraction.
Heart contracts, arteries expand. Left ventricle stops contracting, arterial pulsation ceases. Diastole of the arteries corresponds to systole of the heart. I nductive arguments , unlike deductive syllogisms , require additional support sometimes referred to as warrants . P rimarily a summary chapter in which Harvey begins to suggest a broader circulatory system hypothesis.