Scholars continue to be fascinated by the question of when Homer composed the Iliad, and one recent study even applied mathematics to try to pinpoint its date. There are numerous ways of investigating this, such as examining artwork on pottery, ancient texts about Homer’s contemporaries, and clues within the poem itself. But how does this mathematical approach work?
Principles behind the mathematical approach to dating Homer’s Iliad
The study was conducted by researchers from the University of Reading, and it was published in the journal BioEssays in 2013. More recently, in August 2025, the same lead researcher, Mark Pagel, published an explanation of the same process and results in Medicine in Homer.
How did this study work? The study relied on comparisons between three languages. One was Homeric Greek, the second was Modern Greek, and the third was Hittite. This last language was the language of the ancient Hittite Empire in Bronze Age Anatolia.
Since Hittite, like Greek, is an Indo-European language, it has a so-called genetic relationship to the language of Homer. That is, both Greek and Hittite descend from a common ancestor. This means that by comparing these three languages, we can use mathematics to work out when Homer wrote the Iliad.
Language changes
How does this comparison actually work? According to the researchers, the study used “shared cognates among Hittite, and Homeric and Modern Greek, and rates of lexical replacement in Indo-European languages.”
The researchers took into account the rate at which the vocabulary of a language changes over time. While words constantly evolve, what is less common is a word being replaced by an unrelated word. For example, the word “hund” (now “hound”) was generally replaced by the unrelated “dog” in English several centuries ago.
The average half-life for any given word is about 2,500 years. That is, there is about a 50 percent chance that a word will be replaced by an unrelated word within two thousand to three thousand years. However, this is only the average, and the true rate varies significantly depending on the word. As the researchers explained:
“We associated with each word its rate of lexical replacement (the rate at which a word is replaced by a new unrelated or non-cognate word) in the Indo-European languages. We then estimated the time separating pairs of vocabulary sets by seeking the times in years that simultaneously maximized the likelihood of observing these distributions of cognacy judgements, on the phylogeny in Fig. 1A, given their rates of lexical replacement.”
In other words, they looked at the vocabulary of Hittite, Homeric Greek, and Modern Greek. By using the rate at which certain words are known to be replaced, they could estimate when Homer must have written the Iliad.
When Homer wrote the Iliad according to mathematics
What were the results of this study? When, according to mathematics, did Homer write the Iliad? The ultimate result was that, with 95 percent confidence, Homer appears to have written the Iliad in approximately 762 BC.
In reality, the story is more complex. The study’s initial result was somewhat different: the mathematics suggested that Homer wrote the Iliad in 707 BC. The researchers then noted, however, that this first analysis relied solely on linguistic data and did not take any historical information into account.
One key piece of historical information is that Herodotus mentioned Homer. Herodotus was a Greek historian of the fifth century BC. This means that Homer and the Iliad must predate 450 BC.
To account for this, the researchers repeated the study using an adjusted mathematical model, using a bell-shaped initial estimate for Homer’s age, most likely around 800 BC. This allowed for a range of about 200 years on either side. By starting from this assumption in their Bayesian analysis, 450 BC would fall outside the most likely range of dates for Homer.
This second analysis yielded a date of 762 BC, leading the researchers to conclude that, based on the mathematics, this was the most probable time when Homer composed the Iliad.
Issues with this study
Undoubtedly, this is a fascinating study. Most scholars place the composition of the Iliad in either the eighth or seventh century BC, and even without historical evidence, the study arrived at a date fully consistent with this range.
Therefore, this study shows that mathematical models of language change can be used effectively, as they do seem to provide reasonable estimates for when ancient texts were composed.
However, we must also be cautious. The figure of “95 percent confidence” actually covers a very wide range of possible dates, with 762 BC being only the most likely. It would be misleading to treat this result as anything close to a precise date for when Homer composed the Iliad.
If one were to cite a date from this study, it should in fact be 707 BC rather than 762 BC. The former was the raw mathematical result, whereas the latter emerged only after the researchers assumed that Homer lived within two centuries either side of 800 BC.
While it is almost certain that he did live somewhere within that range, the problem lies in the arbitrary choice of 800 BC as the center of their estimate in the Bayesian analysis. Had they instead centered Homer’s age on 700 BC with a standard deviation of 100 years, the mathematical outcome would naturally have been different.
Thus, we cannot say that mathematics proves Homer composed the Iliad in 762 BC. Nevertheless, the results of this study remain broadly consistent with the conclusions of historians on the matter.
