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Herodotus and Thucydides Through the Lens of Aristotle


The Hippopotami and the Plague

by Ben Zarit
May 9th, 1995

Table of Contents

  1. Introduction
  2. Herodotus and Aristotle
    1. The Crocodile
    2. The Hippopotamus
    3. Similarities
  3. Thucydides and Aristotle
    1. Thucydides and the Plague of Athens
    2. Thucydides and the Revolution at Corcyra
    3. Aristotle on the Male Role in Reproduction
    4. Aristotle on the Teeth
    5. Similarities
  4. Conclusion
  5. Comments on this paper


Herodotus' The Histories chronicled the events of the war between Greece and Persia in the late sixth and early fifth centuries, as well provided a detailed background and description of many of the lands involved in the conflict. Thucydides' History of the Peloponnesian War chronicles the struggle between Athens and Sparta in the years 431 BCE until 404 BCE. Herodotus (c. 480 - 425 BCE) approached his history by trying to give as much information as possible, regardless of whether it was directly related to the subject. He presents the reader with many details, often offering conflicting stories. Thucydides (c. 460 - ? BCE), on the other hand, tends to give a specific description of an event and then draw use that event to draw more general conclusions based upon his observations and the evidence he has available.

In Aristotle's On the Parts of Animals, before he begins his discussion, he asks

"should one take each being singly and clarify its nature independently, making individual studies of, say man or lion, or ox and so on, or should one first posit the attributes common to all in respect of something common?" (Parts of Animals 639a16).
The first statement, taking each being singly, reflects the way Herodotus' would have approached this work. Had Thucydides written the same work, he would have focused more upon the second statement, that of positing the common attributes, and them drawing conclusions based upon observation and evidence. Aristotle definitely read Herodotus because in his Historia Animalium , he says at one point, "Herodotus is mistaken when he writes that the Ethiopians emit black semen." (Historia Animalium 523a17) which refers to Herodotus' statement "Their [the Ethiopians] semen is not white like other peoples', but black like their own skins." (Herodotus, 3.101.2). Most likely Aristotle had read Thucydides or least was familiar with his work as well. Aristotle's works, particularly his ones dealing with animals and nature reflect, either intentionally or not, both Herodotus' and Thucydides' style.

Herodotus and Aristotle

The Crocodile

Pictures from The Handbook of Alligators and Crocodiles by Steve Grenard. Krieger Publishing Company, Malabar, Florida 1991.
Photo on the left courtesy of Robert T. Zappalorit/Naure's Images.
Photo on the right courtesy of Atagawa Tropical and Alligator Cargen, Shizuoka, Japan.

Herodotus and Aristotle offer very similar descriptions of the Nile crocodile (Crocodylus niloticus). Herodotus says that the crocodile has "pigs' eyes" (Herodotus, 2.68.3) and that the crocodile "is blind in the water but very keen of sight in the air." (Herodotus, 2.68.4). Aristotle's description of the vision of a crocodile bares many similarities with Herodotus'. According to Aristotle, "crocodiles have the eyes of a pig...They see poorly under water, but above water their sight is excellent." (Historia Animalium, 503a8). Herodotus and Aristotle use nearly the exact same phrasing when describing the crocodiles' eyes and vision. Herodotus and Aristotle also both remark upon the fact that the crocodile spends the day on the land, but sleeps in the water. Herodotus says the crocodile "spends the greater part of the day on dry ground, and the night in the river, the water being warmer than the air" (Herodotus, 2.68.1) while Aristotle says "[the] day they [the crocodiles] spend for the most part on land, but the night they spend in the water, because it is warmer than the open air" (Historia Animalium 503a10).

Herodotus and Aristotle both comment upon the relationship the crocodile was thought to have with one of the species of birds that also dwells in the Nile area. Herodotus remarks that

"[since] it [the crocodile] lives in the water, its mouth is all full of leeches. All birds and beasts flee from it, except the sandpiper, with which it is at peace because this bird does the crocodile a service; for whenever the crocodile comes ashore out of the water and then opens its mouth (and it does this mostly to catch the west wind), the sandpiper goes into its mouth and eats the leeches; the crocodile is pleased by this service and does the sandpiper no harm." (Herodotus, 2.68.4)
Aristotle describes the same relationship in the following way:
"When the crocodiles gape the trochilos fly in and clean their teeth, and while they themselves are getting their food the crocodile perceives that he is being benefited and does not harm them, but when he wants them to go he moves his neck so as not to crush them in his teeth" (Historia Animalium, 612a21).
Further, Herodotus relates that some Egyptians consider the crocodile sacred. He says,
"Some of the Egyptians consider crocodiles sacred; other do not, but treat them as enemies. Those who liver near Thebes and lake Moeris consider them very sacred. Every household raises one crocodile, trained to be tame;" (Herodotus, 2.69.1).
Aristotle's statements on this subject differ slightly in that he offers an explanation of why the crocodiles become tame. He says
"This is made clear by the way animals are looked after in Egypt; for because food is available and they are not in want, even the wildest animals live with each other; for they become tame because of the benefits given to them, for example in some places the crocodile kind has become tame towards the priest because their food is looked after" (Historia Animalium, 608b31).
Both of the descriptions of the crocodile reflect similar concerns: the appearance of the creature, its habits and its relationship to its environment.

The Hippopotamus

Picture from The collins Guide to the Rare Mammals of the World by John A. Burton. The Stephen Greene Press, Lexington, MA. 1987.

Herodotus and Aristotle description of other animals share many similarities as well. Herodotus offers this description of the hippopotamus:

"They [the hippopotami] present the following appearance; four-footed, with cloven hooves like cattle; blunt-nosed; with a horse's mane, visible tusks, a horse's tail and voice; big as the biggest bull. Their hide is so thick that, when it is dried, spearshafts are made of it." (Herodotus, 2.71.1).

Compare that with Aristotle's description of the hippopotamus:

"The Egyptian hippopotamus has a mane like a horse, is cloven-hoofed like an ox, and is snub-nosed. It has a huckle-bone like the cloven-footed animals, tusks which just show through, the tail of a pig, the neigh of a horse, and the size of an ass. Its hide is so thick that spears are made from it. Its internal organs resemble those of the horse and the ass." (Historia Animalia, 502a10).


Both descriptions again focus on the physical appearance of the creature involved, and in fact both use some of the same terminology. The similarity of the descriptions indicates that both men approached the description of the animals with a similar objective: to represent the animal in such a way as to describe it fully to one who had not seen either animal before. From his asides about the animals of the Nile, one can see that a heavily descriptive style characterizes Herodotus' writing. In his descriptions of individual animals, Aristotle's uses a similar style, presenting a clear picture of the animal.

Thucydides and Aristotle

Thucydides and the Plague of Athens

Thucydides takes an inductive approach to the conclusion he draws, basing them upon his own observations and the evidence before him. In the year 430 BCE, Thucydides relates that a plague struck Athens devastating its population. Thucydides, himself a victim of the plague, describes (Thucydides, 2.49.2) the symptoms of the plague in the hope that others will be able to identify it at a later point. He believed that the disease was unlike any other that he had knowledge about. He says "All the birds and beasts that prey upon human bodies, either abstained from touching them (though there were many lying unburied), or died after tasting them." (Thucydides, 2.50.1). He assumes that this disease differed from others because he has observed a distinctive change in pattern of the scavengers.

Thucydides describes who fell prey to the plague in a very general manner. He doesn't offer specific case studies; instead he offers broad conclusions based upon evidence that he has gathered. "Strong and weak constitutions proved equally incapable of resistance, all alike being swept away" (Thucydides, 2.51.3). He also observes that the physicians, while not only unable to find a cure, "died themselves the most thickly, as they visited the sick most often" (Thucydides, 2.47.4). This observation indicates that Thucydides had some knowledge of the method that the disease was spread, an advancement over Apollo's arrows spreading disease, as Homer relates in the Iliad. Contact with a person infected with the plague causes healthy person to be exposed to the plague, with the result being that they to will become infected. He also notices that those who have had the plague, but have survived are immune to the disease. Those who survived the plague were the most willing to help the sick and dying because they "had now no fear for themselves; for the same man was never attacked twice -- never at least fatally." (Thucydides, 2.52.6). Once again, when describing the spread of the plague, he uses his observations to draw general conclusions, instead of relating the specific instances of the plague.

Thucydides also uses the plague to illustrate several conclusions about human nature. He says that men, believing that there was no severer punishment besides the plague, indulge in acts of violence and lawlessness. They did not hold because "fear of gods or law of man there was none to restrain them" (Thucydides, 2.53.4). They observed that the possessions of many rich men who had succumbed to the disease had been left unclaimed, and took this opportunity to fulfill their own desires. They "resolved to spend quickly and enjoy themselves, regarding their lives and riches as alike things of a day." (Thucydides, 2.53.2). The populace observed that all people were falling ill, both the rich and the poor, the pious and the irreverent. There was no punishment that they felt could affect them, seeing as "a far severer sentence had been already passed upon them all and hung ever over their heads" (Thucydides, 2.53.4). Thucydides, as he does latter in dealing with the revolutions that swept all of Greece, tries to offer reasons why the worst side of human nature became the most prevalent one.

Thucydides and the Revolution at Corcyra

Thucydides gives a very specific description about the revolution at Corcyra in the fifth year of the Peloponnesian war (427 BCE), but then goes on to use it as an example of the revolutions that occurred during the remaining portion of the war. He says, "Later on, one may say, the whole Hellenic world was convulsed [by revolution]" (Thucydides, 3.82.1). He tells the reader what occurred during the revolution at Corcyra, how and why it began, as well as the principle events and the general chaos that resulted. Instead of describing the successive revolutions, he merely describes the first, as "Corcyra gave the first example of most of the crimes" that were committed during the revolutions (Thucydides, 3.84.1). From his observations of the events that occurred at Corcyra, he draws several conclusions, both about the nature of the events and human nature itself.

The conclusions Thucydides reaches about human nature from his analysis of the revolt at Corcyra are not very positive. He begins by saying "Death thus raged in every shape; and, as usually happens at such times, there was no length to which violence did not go" (Thucydides, 3.81.5) and then goes on to describe in particular how people's actions and opinions changed. He says that "Words had to change their ordinary meaning and to take that which was now given them" (Thucydides, 3. 82.4) because what had once been considered extreme and unreasonable behavior was know considered accepted. As an example, he offers the fact that "Reckless audacity came to be considered the courage of a loyal ally; pr udent hesitation, specious cowardice" (Thucydides, 3.82.4). He believes that human nature suffers greatly during a revolution, that the worst sides of people are revealed. Rational people during peace, "but war takes away the easy supply of daily wants, and so proves a rough master, that brings most men's characters to a level with their fortunes" (Thucydides, 3.82.2). Thucydides describes the revolution at Corcyra, exams the evidence provided by careful observation, and from there draws the conclusion that "human nature, always rebelling against the law and now its master, gladly showed itself ungoverned in passion, above respect for justice, and the enemy of all superiority" (Thucydides, 3.84.2).

Aristotle on The Male Role in Reproduction

In his discussion of biology, Aristotle does not deal with the same topics as Thucydides did in his history. However, in his On the Generation of Animals, he uses many of the same techniques Thucydides used to describe the plague and the effects of revolution upon human nature. He differs from Thucydides in that he often states his reasoning before he presents the evidence, but, like Thucydides, he does relate the evidence and then draws his conclusions.

In chapter 21 of the second book of his On the Generation of Animals, Aristotle discusses the function males have in reproduction, which Aristotle proposes to determine both through reason and the facts. His reasoning is some what difficult to follow, but after stating that the male contributes the "capability and movement" (Generation of Animals, 729a6) of the offspring, he tells the reader that the male is the agent and the mover while the female is the patient and the moved. The offspring receives its form from the agent, while the substance comes from the patient, similar to how a "bed is out of the carpenter and wood" (Generations of Animals, 729b17).

However, after he gives his intellectual argument, he supports his theory with facts gleamed from observation of the reproductive habits of different animals. He gives insects as his first example, because certain males "are seen to put no part into the female, but on the contrary the female is seen to put a part into the male." (Generation of Animals, 729b24) This supports his theory in that the male does not contribute substance to the offspring, because in this particular case, the female does not receive anything from the male, at least as far as Aristotle can tell. Instead, the reproduction comes about because "the heat and capability in the animal [the male] itself when the female brings into it the part that is receptive of the residue." (Generation of Animals, 729b26).

His second example deals with birds and oviparous kinds of fish. In this case he says "the male does not emit any part such as will remain present within the offspring, but generates an animal merely by the capability in the semen." (Generation of Animals, 730a1). Again the male does not contribute substance to the offspring, at least none that will remain or be of any importance. He concludes that "by its capability the male seed puts matter and nutriment that is in the female into a particular kind of state" (Generation of Animals, 730a15) because Aristotle knows that the male has to be involved somehow with the reproductive process. He reasons that the male must contribute something, since "the female does not generate by itself." (Generation of Animals, 730a28). His conclusion that he reaches is that "the male contributes a source of movement and the female the matter." (Generation of Animals, 730a27). He uses two specific examples to support his theory of reproduction which he then applies to all animals. He generalization has evolved through his observation and study of many particulars.

Aristotle on The Teeth

In chapter eight of the fifth book of Generations of Animals, Aristotle discussion moves to teeth and why the front teeth form first and shed, while the back teeth form later and do not shed. He states that suckling contributes nothing to the formation of the teeth, but the heat to the milk makes the teeth appear more quickly. Aristotle makes this statement in order to disagree with Democritus, who, according to Aristotle, has said
"the early teeth are shed because they are formed in animals too early, for it is when animals are practically in their prime that they grow according to nature, and suckling is the cause he assigns for their being found too early." (Generation of Animals, 788b12).
As evidence, he offers the example of the pig which does not shed any teeth, and saw-toothed animals which all suckle, some of whom shed only their canine teeth, such as lions. He says that the heat of the milk causes the teeth to appear more quickly because that "in suckling animals those young which enjoy hotter milk grow their teeth quicker" (Generation of Animals, 789a5).

The front teeth appear before the back teeth because

"their function is earlier (for diving comes before crushing, and the flat teeth are for crushing, the others for diving), in the second place because the smaller is naturally developed quicker than the larger...and these teeth are smaller in size than the grinders, because the bone of the jaw is flat in that part but narrow towards the mouth." (Generation of Animals, 788b31).
His reasoning, though it may seem a bit arbitrary, comes about because he of the evidence he has observed, namely that the front teeth are smaller and that the jaw is narrow towards the front of the mouth as well as the function of the teeth.

Finally, his gives the reason behind why the front teeth are shed, while the flat ones are not. According to Aristotle,

"while the roots of the grinders are fixed where the jaw is flat and the bone strong, those of the front teeth are in a thin part, so that they are weak and easily moved. They grow again because they are shed while the bone is still growing and the animal is still young enough to grow teeth." (Generation of Animals, 789a10).
The front teeth fall out because the jaw has less strength and less nutritive substance in the front weaker up front. Therefore they are less strong and fall out and are replaced. The evidence from which he draws this conclusion is that "the flat teeth grow for a long time, the last of them cutting the gum at about twenty years of age" (Generation of Animals 789a15). In this case, Aristotle has answered the question he posed at the beginning of the section by uses examples to prove his theories.


While Thucydides and Aristotle discuss very different subjects in The History of the Peloponnesian War and The Generation of Animals, they have a similar style. Thucydides presents the evidence and his observations and then draws his conclusions. Aristotle states his reasoning, presents the evidence and then supports his conclusions. Both make attempts to find generalizations that can be applied outside of the specific examples that they cite.


Herodotus and Thucydides do not present their respective histories in a similar manner. Herodotus often goes off on elaborate diversions upon which ever subject interests him. His work contains not just history, but also contains extensive details about particulars. Thucydides sticks to a political history of the Peloponnesian War, rarely going off on tangents. Instead he tries to find broad generalizations that he can apply to other situations based upon the evidence that he has gathered. Aristotle's works contain elements of both men's style. When appropriate, he uses Herodotus' approach, giving specific details. Other times, he uses Thucydides' approach and tries to find constants that he can state apply to all animals, not just specific ones. Aristotle shows excellent judgment in knowing where to apply each style and significantly improves his work by taking advantage of both of them.