The Origins of Ancient Greek Science

Blood—A Philosophical Study

Michael Boylan

• Publisher: Routledge
• Year: 2015
• Print ISBN: 9780415843935
• eBook ISBN: 9781135013288
• Edition: 1
• Topic: History
• Subtopic: Ancient History
• Index: History

This book examines the origins of ancient Greek science using the vehicles of blood, blood vessels, and the heart. Careful attention to biomedical writers in the ancient world, as well as to the philosophical and literary work of writers prior to the Hippocratic authors, produce an interesting story of how science progressed and the critical context in which important methodological questions were addressed. The end result is an account that arises from debates that are engaged in and "solved" by different writers. These stopping points form the foundation for Harvey and for modern philosophy of biology. Author Michael Boylan sets out the history of science as well as a critical evaluation based upon principles in the contemporary canon of the philosophy of science—particularly those dealing with the philosophy of biology.

1 Blood, Magic, and Science in Early Greek Thought

What is there about blood that makes it an essential ingredient in accounts of the human experience from medicine to poetry? This chapter will explore some of the understandings in early Greek thought about blood, the heart, and blood vessels from the time of Homer to Hippocrates.¹ Since this marks what is generally understood to be the period from pre-natural philosophy to its initial development from Thales onward, most of the comments in this chapter will be suggestive and interpreted against the background of the subsequent history of science and theoretical issues in the philosophy of science.

In order to structure this journey, it will be the strategy of this treatise to concentrate on several key passages that are illustrative of a developing biomedical understanding of the blood and its relationship to the body. For the most part, the chapter will proceed chronologically examining principally texts from Homer² up to the Hippocratic Writers (viewing these as our historical points of departure and arrival).

Let us begin with Homer and pre-natural philosophy. In the Homeric texts, blood is often associated with ichor. These are related concepts. Blood is a very basic fluid for human life. It doesn’t take long for peoples prone to warfare to discover the coincidence of slashing blows that release great quantities of blood and the victim’s consequent death.³ Thus, from the outset, blood is seen to be a vital fluid. Vitality is, by its very nature, mysterious—it constitutes the difference between life and death. For this reason, ancient writers would interpret this mystery by ascribing the possession of various virtues and vices to blood along with powers of procreation and sometimes even the source of thought itself. In this survey of texts, the primary character of blood will be sketched out along with a critical analysis of the terms of these attributions.⁴

Ichor is a substance that seems to exist within blood. In some contexts the mode of this existence is as the watery part of the blood.⁵ In these contexts, ichor is cited as providing some key material property of blood. Thus, in our exploration of blood we must also include ichor.

Blood is associated with courage (a virtue).⁶Ichor in one context is connected to the gods as being their substitute for blood (i.e., humans have blood and the gods possess ichor).⁷ In the Iliad we find:

• … and blood immortal flowed from the goddess,
• ichor, that which runs in the veins of the blessed divinities;
• since they eat no food, nor do they drink of the shining
• wine, and therefore they have no blood and are called immortal.
• (V: 339–442, cf. 416)⁸

The gods are above mortals. One sign of this is their possessing only ichor in their blood vessels instead of a mixture of blood and ichor. This passage thus indicates a certain stature of the fluid mixture within the blood vessels, phlebes, of the body. In its extreme form, it confers the attribute of divinity. What could confer higher excellence (arête => agathos/kleos)?⁹ Thus, the fluid within our blood vessels can confer or contribute to virtue. But what does this mean? Is the mere possession of blood a sufficient condition to produce virtue? The operation of such a process in this context introduces a worldview in which the divine and the material come together side by side to offer sometimes complementary and sometimes redundant explanations.¹⁰ If this is correct (and there are some narrow conditions here),¹¹ then natural accounts of blood and its functioning will be conditioned by both.¹² Perhaps the red fluid that flows forth from war wounds is a natural entity (call this phusis₁).¹³ One way to understand blood is via its material efficacy as nourishment only. But in very early contexts (pre-500 BCE) to say that biomedical events were produced materially also invoked chance (a sort of magical serendipity devoid of divinity)—later (from Aristotle and the Hippocratic Writers onward), this becomes the position of a material/mechanistic view of nature’s material operation. But here phusis₁ is a complicated combination that features material properties but does not exclude mysterious, magical elements either via the agency of chance.

Another way to understand blood is via its added powers when ichor is added to the mix. This new mixture invokes another sense of nature: a divine, super-nature (call this phusis₂).¹⁴ Super-nature is aligned with magic and the divine. Because it is inscrutable, there can be no external examination of it save in the context of a religious setting. Some writers on ancient science and magic such as Dodds, Hankinson, Thivel, Lloyd, Carastro, Gordon, Collins, Nutton, and Edelstein have catalogued numerous instances of magic and the divine (though in different accounts)—particularly in the context of the Hippocratic Writers (our historical terminus in this chapter).¹⁵

It is my contention that the philosopher of science has three options when confronting an event that does not have a clear material cause: (1) to say that it was produced materially though featuring chance (a sort of magical serendipity devoid of divinity), phusis₁,¹⁶ or (2) that it was directly caused by a divinity, phusis₂¹⁷ (sometimes referred to as magic in a direct sense), or (3) that it was caused by unexplainable factors (also sometimes called magic) that are linked only metaphorically to divinity or metaphorically to a material cause, phusis₃.¹⁸ The sense of magic in phusis₁ and phusis₃ are similar. In each case there is no direct tie to divinity as there is in phusis₂, but there is a paucity of information. In phusis₁ this lack of material information logically pushes the practitioners to asserting another causal entity: chance. Now chance, as is well known throughout human history, often has a flirtatious relationship with magic.¹⁹

With phusis₃ the situation is not the presence of “chance,” but rather the lack of critical information so that although it seems clear that there are forces at work, their exact identity is unknown. Since explanatory reason abhors a vacuum, in steps magic (metaphorically) to fill the void.

These three cases represent a common response to inexplicable natural events. But these responses need further conceptual analysis.

Underlying these three responses are worldviews that situate epistemology and metaphysics as being of a certain character. In the first instance phusis is understood materially. Now this is rather broad—especially in the pre-Hippocratic Writers. Often, one sort of material was given preference—such as ‘air, aer’ which becomes pneuma (an active vital force that can be mixed with blood or possess its own system of transmission).²⁰ However, if we agree that one important component in espousing natural philosophy is to present the way causation works materially, then the movement towards greater first-order input at this level is crucial. By “first-order” what is meant is an account at the level of actual occurrences.²¹ For example, if someone gets a fever and there is a suggested diagnosis, prognosis, and treatment in terms of bodily fluids being out of balance (in the context of explanatory theory) and that diet intervention is necessary, then we have an instance of first-order material interventions against a materially caused condition to effect a material outcome (the cure). This is phusis₁. We are in the realm of explaining a material explanandum with a material explanans.

In phusis₂ Divinity is set out as the principal cause. Theoretically, appeal is made generally to the creative power of god(s)—or to specific gods such as Asclepius.²² In the context of metaphysical realism, god(s) actually intervenes in the earthly realm concerning the causes and outcomes of disease. Though god(s) is inscrutable in this activity, the understanding is that god(s) is really a causal agent—not just generally in the creation of everything, but in this particular fever that Antipater is suffering. Petitionary prayer and interaction with priests in an asklepieion is what will bring about a cure.²³ We are in the realm of explaining a material explanandum with a real, nonmaterial explanans.

In phusis₃ we enter the anti-real. Epistemological anti-realism refers to a position in which statements about how we know things about the world are situated within a radical skepticism about the ability to know anything with certainty because the objects of knowledge are either not stable or are unattainable.²⁴ In epistemological anti-realism, one moves away from assumed actual causes (be they material or nonmaterial) to linguistic devices of “als-ob” or heuristic discourse.²⁵ In the history of the philosophy of science, heuristic reasoning may or may not have any real connection to the world. Some very prominent philosophers have asserted that causation, for example, is not necessary (here a code word for real), but rather is a rule of thumb to guide conduct in the world.²⁶ Science in...

Table of contents

• Cover
• Title
• Copyright
• Contents
• Preface
• Acknowledgments
• 1 Blood, Magic, and Science in Early Greek Thought
• 2 The Hippocratic Period—Philosophy versus Clinical Biomedicine
• 3 Aristotle—The Origin and Function of Blood and Body Parts
• 4 Hellenistic, Alexandrian, and Roman Methodological Battles
• 5 Galen—The Grand Synthesis
• Glossary of Philosophical Terms
• Bibliography
• Names and Subjects Index
• Texts Cited Index