On the Sacred Disease, written around the late fifth or early fourth century BCE and preserved within the Hippocratic Corpus, is one of the most important surviving texts in the history of epilepsy. Its importance does not lie in having ‘discovered’ epilepsy. Seizures had been observed and described for many centuries before it, including in Mesopotamian medical texts. Nor can the work be securely attributed to Hippocrates himself. The surviving Hippocratic Corpus was produced by more than one writer, and modern scholarship generally treats the author of On the Sacred Disease as unknown.
What makes the treatise historically remarkable is something more precise: it argues that the condition commonly called the ‘sacred disease’ should be understood through natural causes rather than as a uniquely divine affliction requiring magical explanation.
The Hippocratic Corpus is not the work of one author
The name Hippocrates has become shorthand for an entire tradition of Greek medicine, but the Hippocratic Corpus is a collection of dozens of works written over a long period, mostly between the fifth and fourth centuries BCE, with some material later. The texts differ in style, theory and medical opinion.
Hippocrates of Cos was almost certainly a real physician of the classical Greek world, but historians cannot simply assume that every work transmitted under his name was personally written by him. On the Sacred Disease is therefore best described as a Hippocratic treatise rather than a securely authenticated personal work of Hippocrates.
This distinction matters because later medical history repeatedly turned Hippocrates into a symbolic founder figure. The actual history is more complicated: the text reflects a wider intellectual movement toward observation, argument and natural explanation within Greek medicine.
What was the ‘sacred disease’?
The Greek expression translated as ‘the sacred disease’ referred to a condition strongly associated with convulsions and what modern readers would recognise as epileptic seizures. The title reflects the cultural environment in which unusual attacks could be interpreted through divine action, pollution, possession or supernatural influence.
The author opens by challenging the idea that the disease is more divine than other illnesses. He argues that its apparently sacred status arose because people found it extraordinary and difficult to understand. In other words, the mystery of the symptoms had encouraged supernatural explanations.
This was not a denial of religion in the modern sense. The argument was subtler. The writer rejected the claim that this particular illness had a special supernatural cause requiring ritual treatment. Disease, in his framework, followed regular processes within nature.
A direct attack on magical healers
Much of the opening section is polemical. The author criticises healers who claimed to treat the disease through purification, incantation, ritual prohibitions and other supernatural practices.
He argues that these practitioners protected themselves from failure by blaming the gods or the patient. If someone recovered, the treatment received credit; if the person did not recover, the divine nature of the illness could be blamed instead.
The text therefore offers more than a theory of epilepsy. It is also evidence of competition between different kinds of healers in ancient Greece. Rationalising physicians did not operate in a world where supernatural medicine had simply disappeared. They argued against other practitioners who continued to interpret illness through ritual and divine agency.
The brain was placed at the centre of the disease
One of the most historically significant features of On the Sacred Disease is its insistence that the brain is central to the disorder.
The author regarded the brain as the organ through which sensation, understanding, emotion and behaviour were mediated. The seizure disorder was therefore located within the same organ that shaped consciousness and thought.
This was a major conceptual step, but it should not be rewritten as modern neuroscience. The explanation offered was based on humoral physiology. The author believed that an abnormal accumulation or movement of phlegm in the brain and blood vessels interfered with the normal movement of air and produced the attack.
The mechanism was wrong by modern standards. Historically, however, the crucial shift was away from a seizure being treated primarily as evidence of divine intervention and toward a bodily process centred on the brain.
What symptoms did the author describe?
The Hippocratic writings contain descriptions that historians and neurologists have compared with several forms of seizure. These include attacks with loss of consciousness, falls, convulsive movements, frothing or salivation, altered breathing and subsequent recovery.
Modern analysis of the collection also suggests descriptions compatible with focal seizures and seizures that begin asymmetrically before spreading. Some passages appear to recognise warning sensations before an attack, which have been compared with what would now be called an aura.
However, retrospective diagnosis must remain cautious. Ancient writers did not use modern electroclinical classifications, and surviving descriptions cannot always distinguish epilepsy from fainting, acute symptomatic seizures, febrile convulsions or other causes of episodic collapse.
Focality and one-sided symptoms
The Hippocratic collection is especially interesting for its attention to laterality. Other Hippocratic texts discussing head wounds describe convulsions occurring on the side opposite a cranial injury.
That observation contributed to a long historical thread linking one-sided bodily symptoms with disease affecting the opposite side of the brain. It would take more than two millennia before localisation became part of modern neurology, but the clinical habit of noticing which side moved, weakened or convulsed was already present.
This is history of observation rather than proof that ancient physicians understood cortical localisation as it is understood today.
Was heredity recognised?
On the Sacred Disease also discusses familial tendency. The author argued that the disease could be inherited, reasoning that bodily characteristics and disease susceptibilities could pass through families.
This is sometimes presented as an astonishing anticipation of modern epilepsy genetics. That interpretation needs restraint. The writer did not know genes, chromosomes or molecular inheritance. Nevertheless, the recognition that susceptibility might run in families is historically important because it placed causation within natural biological continuity rather than divine punishment.
Childhood and the course of the disease
The treatise pays particular attention to age. It suggests that the disease commonly begins in childhood and that outcome varies depending on age and the development of the body.
The author believed that some young people could improve as they matured, whereas long-established disease could become more difficult to cure. This reflects an ancient attempt to think about prognosis rather than treating every seizure as an isolated supernatural event.
Other works in the Hippocratic collection describe convulsions associated with fever and systemic illness, suggesting that ancient physicians may sometimes have distinguished recurrent seizure disorders from seizures occurring during another acute disease.
Diet, environment and treatment
Once the disease was framed as natural, treatment also shifted toward natural interventions. Hippocratic medicine emphasised diet, regimen, exercise, climate, bodily balance and the management of humours.
These treatments were not evidence-based in the modern clinical sense, and many were based on physiological theories that are no longer accepted. Their historical importance lies in the principle that a natural disease should be managed through natural means rather than exorcism or ritual purification.
This does not mean that every ancient Greek physician abandoned religious practices, nor that patients suddenly stopped seeking temples or ritual healers. Medical traditions overlapped for centuries.
The famous goat observation
Later discussion of the treatise often highlights its reference to animals, particularly goats said to suffer from the same disease. The author reportedly noted abnormalities in the brains of affected goats and used these observations to support a cerebral explanation.
The interpretation was still framed within humoral medicine, but historically it demonstrates an effort to connect disease theory with physical observation rather than relying only on supernatural narrative.
Did the treatise end the supernatural view of epilepsy?
No. This is one of the biggest myths in simplified histories of epilepsy.
On the Sacred Disease did not cause the ancient world to abandon supernatural beliefs about seizures. Religious, magical and medical explanations continued to coexist. Later European history repeatedly returned to ideas of possession, sin, witchcraft, divine punishment or spiritual danger.
The treatise therefore represents an important intellectual argument, not a clean turning point after which epilepsy became universally understood as a neurological disorder.
Why ‘Hippocrates discovered epilepsy’ is inaccurate
The statement fails for several reasons.
First, seizure descriptions existed long before classical Greece. Mesopotamian texts contain detailed observations centuries earlier.
Second, epilepsy is not a single discovery like an isolated anatomical structure. Human beings had observed recurrent seizures throughout recorded history.
Third, the authorship of On the Sacred Disease cannot be assigned to Hippocrates with certainty.
Fourth, the treatise’s physiological explanation was historically naturalistic but scientifically incorrect in its humoral mechanism.
A more accurate statement is that the Hippocratic tradition produced one of the earliest surviving systematic arguments that epilepsy had a natural cause centred in the brain and did not require a uniquely supernatural explanation.
Stigma was already visible
The text also tells us something about social reactions to epilepsy. The author’s frustration with ideas of impurity, divine influence and ritual restriction indicates that seizures already carried cultural meanings beyond the physical event itself.
Later scholars have identified passages in the Hippocratic collection that acknowledge fear, shame and behavioural consequences associated with the disorder. That makes the work relevant not only to the history of neurology but also to the much longer history of epilepsy stigma.
The word ‘epilepsy’
The Greek word associated with epilepsy derives from a verb meaning to seize, attack or take hold of. Ancient terminology did not map neatly onto modern diagnostic categories, and different Greek terms could describe convulsion, spasm, seizure or illness depending on context.
The Hippocratic collection is therefore important to the later history of epilepsy language, but it should not be read as if it already contained today’s distinction between focal epilepsy, generalised epilepsy, acute symptomatic seizures and non-epileptic events.
A text at the boundary between religion and medicine
One reason On the Sacred Disease remains historically powerful is that it captures a moment when explanations of illness were being openly contested.
The author did not simply say, ‘the gods do not exist.’ Instead, he argued that calling one disease sacred because its symptoms were frightening or unfamiliar was logically inconsistent. Other illnesses were equally remarkable, yet were not automatically assigned a special divine status.
That style of argument marks an important development in medical reasoning: unusual symptoms did not have to require an unusual supernatural cause.
What changed — and what did not
The treatise helped establish several ideas that would echo through later medical history: that seizures could arise from the brain, that careful observation of symptoms mattered, that disease could run in families, that age and bodily condition influenced outcome, and that natural illness should be approached through natural explanation.
But it did not create modern epilepsy medicine. Humoral theory remained dominant for centuries. Supernatural interpretations persisted. Effective antiseizure drugs did not appear until the nineteenth century. EEG would not arrive until the twentieth century. Modern seizure classification came much later still.
The historical achievement of On the Sacred Disease is therefore best understood on its own terms: it challenged a special supernatural explanation for seizures and argued that even the most frightening and mysterious illness belonged within the natural world.
Why this matters in the history of epilepsy
Epilepsy history is often told as a simple march from superstition to science. The reality is less tidy. Naturalistic and supernatural explanations repeatedly existed side by side, sometimes within the same society and even within the same person’s understanding of illness.
On the Sacred Disease matters because it gives us unusually clear evidence that this debate was already happening more than two thousand years ago.
It did not finish the argument. It documented one of its most important early forms.
Sources and further reading
Hippocratic Corpus — On the Sacred Disease, English translation via Perseus
Theodore WH. Epilepsy in the Hippocratic collection: Seizures and syndromes. Epilepsy & Behavior. 2021.
Wolf P. History of epilepsy: nosological concepts and classification. Epileptic Disorders. 2014.
The evolution of the concepts of seizures and epilepsy: What’s in a name? Epilepsia Open. 2020.
Panteliadis CP et al. Historical documents on epilepsy: From antiquity through the 20th century. Brain & Development. 2017.
Corpus Hippocraticum ‘On the Sacred Disease’. Historical review.
van der Eijk PJ. The theology of the Hippocratic treatise On the Sacred Disease.
Historical evidence checked: September 2026.