Hemlock causes a frothing, spasming Death, and it is by this poison that Socrates was famously executed. However, Plato describes the death of Socrates far more tranquilly in Phaedo. This portrayal typifies the proper philosopher’s death, which respects death as not only natural but as the aspiration of philosophy.

The Poisoning of Socrates

After a trial brought on by sensational charges of corrupting the youth and religious impiety, Socrates is sentenced to death by the Athenian dikasts — a random jury of peers. His is one of the most notable portrayals of historical execution by poisoning, described in Plato’s Phaedo. In this case, the recorded effects of the poison are incomplete if not inaccurate. As Plato recounts, Socrates is administered the Athenian State Poison in wine by a physician-poisoner.

The physician-poisoner instructs Socrates to walk until he feels difficulty. This was a common practice used to speed the travel of the poison to the heart. As the poison begins to take effect, numbing his feet and legs, Socrates lays down on the nearby lounge. The deadening of his body, traveling up from his feet, brings his death. After his final breath, the physician-poisoner closes his eyes (Phaedo 58a-118d).

The Athenian State Poison

Broadly, it seems that poisoning was a culturally congruous affair in Ancient Greece. This is suggested chiefly by the existence of the Athenian State Poison. The Poison was used specifically for capital punishment. In addition to Socrates, several other famous Athenians were also executed using this poison.

To prepare it, seeds of the poison hemlock plant were pounded in a mortar, then potentially modified further with other additions before being mixed with wine for easy consumption. Theophrastus writes that sometimes the juice of the poppy (opium) was also mixed with the hemlock to make the State Poison more narcotic and the death by the poison more tranquil.

Theophrastus also claims the hemlock used was a Cicuta, which was then the general consensus. Most scholars now agree that it was the hemlock Conium maculatum, known colloquially as “poison hemlock”.

C. Maculatum Toxicity and Symptomatology 

Conium maculatum is a plant native to Europe and North Africa. Its toxicity varies depending on the plant’s maturity and environmental factors. Typically, C. maculatum is most toxic in the spring. It contains several toxic piperidine alkaloids, but the most lethal active alkaloid is coniine. The coniine alkaloid affects the central nervous system directly, often causing death via respiratory paralysis.

Symptoms progress through stimulation and into depression. The victim experiences nausea and vomiting, excessive salivation and sweating, abdominal pain, tachycardia, ataxia, tremor, headache, dizziness, muscle fasciculations, and tremors, then hypotension and bradycardia, depression of the central nervous system, muscular weakness and/or paralysis, respiratory distress and arrest, and coma. A lethal human dose is between five and eight grams of leaves.

Medical Inaccuracies in the Death of Socrates

According to Plato’s Phaedo, the clinical symptoms that Socrates experiences are: numbness of extremities, weakness of extremities, muscle paralysis, sedation, and finally death. Except for the peculiar case of numbness (while C. maculatum poisoning can cause centripetal paralysis, it does not cause numbness), these others are all common symptoms of Conium maculatum poisoning. Coniine depresses the nervous and respiratory systems.

Modern case reports of poisoning by C. maculatum recount less peaceful experiences. In his account of the execution of Socrates, Plato overemphasizes effects such as paralysis and sedation, ignoring the less tasteful symptoms which Socrates would have almost surely experienced. Even in reports concerning C. maculatum poisoning, which do not describe overly disruptive symptoms preceding the coma, the patient still encounters additional symptoms while comatose.

One case report describes a 59-year-old man — only a decade younger than Socrates, who was executed at 71 — who mistakenly ingested C. maculatum. The patient’s relatives informed doctors that within thirty minutes after ingestion, the patient experienced headache and weakness in the lower limbs as well as difficulty breathing. Then he lost consciousness. He was admitted to the emergency department three hours after C. maculatum consumption, still comatose. Broadly, this account aligns very well with Plato’s, except that upon falling unconscious, Socrates dies while, fortunately, our patient does not. (After two days of intensive care, this patient recovered.)

Despite these consistencies, there are key effects of C. maculatum poisoning left out of Plato’s death of Socrates. While comatose, the patient experiences additional symptoms, such as excessive salivation and involuntary muscle spasms called ataxia. According to Plato, these common effects of C. maculatum do not exist–they are not included in the Phaedo.

The Departure of Socrates’ Soul

Plato chooses to depict Socrates as noble against adversity and removes any factors which might introduce indignity. When he dies, Socrates lies on his deathbed still and uncorrupted like a Catholic saint. This portrayal exalts Socrates himself by fulfilling the broader conventional expectation of a philosopher’s death.

Plato says that the philosopher’s soul must: “…Follow reason and be always engaged in [philosophy], contemplate the truth, the divine…and be nourished by it…” And of the death of the philosopher who embodies that soul, he claims that “from such nurture and having practiced these things…there is no danger that [the soul] will fear that, torn apart in its separation from the body it may depart…and no longer be anything anywhere at all” (Phaedo 84a-b).

In other words, for Socrates to show fear of his death or pain during it would undermine the paramount knowledge that true philosophers possess: that death is in fact the freedom which all philosophers seek. Death is the extrication from the body and, finally, the full engagement with the soul.

Plato’s Socrates puts a fine point on this concept using an analogy to swans and their songs:

“When [the swans] perceive that they must die…they now sing at their loudest and most beautiful, rejoicing in the fact that they’re about to go to the god whose servants they are. But human beings, because of their own fear of dying, interpret the swans wrongly and say they’re lamenting death…and they don’t take into account that no bird sings when it is hungry or cold, or suffering any other kind of distress…”

He finishes: “Nor am I any more downhearted than [the swans] are in giving up my life” (Phaedo 85a-b).

So Socrates makes his confident descent into the unknown frontier of death. Though Crito urges him to wait to drink the pharmakon, Socrates refuses, and takes it as soon as it is prepared. Then that medically inexplicable numbness overcomes him, moving from toe to head. Scholar Christopher Gill explains it thusly in The Death of Socrates:

“The word [psyche], usually translated as “soul”, had a number of meanings, as the essential functions of life were variously identified. Sensation, however, was generally seen to be a product of psyche… Since Homer, loss of sensation, in fainting and death, had been described as psyche leaving the body.”

From the departure of feeling, the Platonian audience would have understood that the soul was experiencing its liberation from the shackles of the human body. Plato not only presents Socrates as a courageous man and a true philosopher, but he also describes scene by scene the prototypical, instructive philosopher’s death. Death is the culmination of philosophical study. In his own words:

“Other people are likely not to be aware that those who pursue philosophy correctly study nothing but dying and being dead. Now if this is true, it would be absurd to be eager for nothing but this all their lives, and then to be troubled when that came for which they had all along been eagerly practicing”
(Phaedo 64a).