In the world today, few mysteries remain as inexplicable as death,
a subject that has perplexed and divided our society for thousands of years. Some cultures and
religions describe an afterlife where souls pass between ethereal realms, while others conceive
of death as little more than a sudden drop into nothingness. Almost universally, death is a great
unknown awaiting all living things at the end of existence. So what really happens when you die?
After death, the body experiences a cascade of physical changes, largely dependent on the time,
location, and cause of death. The process typically begins with a total loss of respiratory,
cardiac, or neurological function. In one way or another, the heart ceases beating,
respiration stops completely, and the brain, once it is deprived of oxygen,
begins to shut down. Within the first hour after death, muscles throughout the body begin to relax,
entering a state known as primary flaccidity. Soon, the skin becomes pale, and body temperatures
drop to match the surrounding environment. Within 1 to 6 hours, muscles and joints become rigid,
starting with the small muscles in the face, which typically mark the onset of rigor mortis.
As the systems that govern the physical body grind to a halt, all electrical activity terminates in
the brain, and the contents of the mind are permanently lost. A lifetime of memories,
knowledge, and experiences seem to vanish. In some ways, the death of a person is similar to
the total systematic failure of a computer. Unless the information from that computer is stored
elsewhere, its contents exist in no other world or dimension. Once a computer’s hardware stops
functioning, its contents disappear forever. The human brain may function in a similar way, which
leads many people to wonder: do our lives lose all meaning and significance at the moment of death?
Religious traditions present several opposing hypotheses that deny the apparent meaninglessness
of strictly scientific interpretations of death. For instance, many belief systems
consider the significance of our lives on Earth by conceiving of humans as dualistic beings
with material bodies and immaterial spirits or “souls.” At the moment of death, the physical
body may perish completely, but many religions believe our non-physical souls continue to exist.
If humans are truly dualistic beings, possessing both a body and soul, what becomes
of our disembodied souls after death? How do our fleeting lives on Earth influence our potentially
eternal journey beyond the grave? In Christian traditions, two or sometimes
three realms of the afterlife — Heaven, Hell, and Purgatory — await all souls as compensation for
their earthly deeds. At the moment of death, the soul leaves the physical body to stand before God
and receive divine judgment. According to God’s will, good, righteous people are delivered to
Heaven, while unrighteous people, as well as those who reject God’s love, must spend an eternity in
Hell. All other souls, including sinners who put their faith in God, travel to a realm of temporary
punishment called Purgatory, where they are purged of their sins and eventually welcomed into Heaven.
Though Heaven and Hell are described in the Bible as physical places, many Christians
interpret the realms of the afterlife as the subjective experience of God. People
in Heaven experience God’s eternal love, while people in Hell forever suffer in God’s absence.
Concepts like Heaven and Hell are shared by most Abrahamic religions, including Christianity,
Islam, and Judaism. Among them, Islam is perhaps the most descriptive. In Islamic traditions,
life after death is known as Akhirah and begins when the soul is drawn out of the body by Azra’il,
the angel of death. The soul is then tested on the teachings of the Qur’an by two ambassadors
of Allah, the omnipotent God of all things. Believers in the Qur’an are admitted to a
paradise called Jannah, whereas unbelievers are punished in Jahannam, forced to wear
garments of fire, and doused in boiling water. Almost all major religions draw connections
between the afterlife and one’s actions on Earth. People who do good things are typically rewarded
for their virtuosity, while people who do bad things receive some kind of punishment. However,
major religions disagree on the notion of an everlasting afterlife. While Abrahamic
religions create a clear divide between life on Earth and life after death,
some Eastern traditions view life and death as semipermanent stages in a great, cosmic cycle.
For example, Buddhist teachings revolve around reincarnation, a cyclical process through which
non-physical souls are reborn as other living entities. Throughout their infinite lifetimes,
souls accrue moral attributes or karma based on how they lived their lives.
With each life cycle, good karma brings souls closer to nirvana, a state of higher being or
enlightenment that releases souls from samsara, the endless cycle of life, death, and rebirth.
Hindu interpretations of death and the afterlife share many core concepts with Buddhism,
including samsara and the accruing of karma over multiple lifetimes. Hindu traditions relate the
process of life and rebirth to wearing a new set of clothes. The physical body
changes but the essence of the self, known as the atman, endures into the next life.
Between death and reincarnation, when the atman is unclothed, it departs from the physical world
on a treacherous journey through the kingdom of Yama, the Hindu god of death. At the end of its
long journey, the atman is judged by Yama and reincarnated into a new body, perhaps a bird,
a bug, or another human being. Over and over, the atman dies and is reborn until,
at last, it achieves final emancipation or moksha, which means “life everlasting.”
Outside the world’s major religions, there are thousands of unique systems of faith, each with a
distinct perspective on life after death. The ancient Persian religion of Zoroastrianism,
one of the oldest organized religions in the entire world, describes a narrow bridge
that disembodied souls must cross to enter their version of paradise, known as the House of Song.
In some traditional African religions, the souls of the dead remain connected to their relatives
as spiritual ancestors and, in some cases, are reborn into their families as newborn children.
These religious traditions offer an array of futures for departed souls; however,
science and secular philosophy have cast doubt on the existence of a soul in the human body.
Early philosophers regarded the human soul as an anatomical fact, but the soul largely
disappeared from academic texts once the brain was identified as the source of our physiological
processes and cognition functions. Thus, the “mind” replaced the soul as the primary force
behind human reason, cognition, and free will. However, concepts of the soul and the afterlife
are still helpful metaphors for human psychology and individual consciousness.
At the moment of death, literal spirits may or may not rise from our bodies. Either way,
humans may experience some form of postmortem existence, if only for a few short seconds.
Recent studies have detected rhythmic wave patterns, like those measured while dreaming
or meditating, in brains that have suffered cardiac or respiratory cessation. Additionally,
many individuals who survive near-death events have reported profound experiences,
including auditory and visual sensations, while teetering on the brink. Some people
encountered bright lights and hallucinations, while others underwent out-of-body experiences,
during which their spirits seemed to separate from their corporeal selves. Postmortem brain activity
hardly proves the existence of an afterlife, but it does raise questions about the subjective
experience of death. More importantly, it exposes gaps in our knowledge of human psychology,
consciousness, and the great beyond. Precisely what form postmortem existence
takes is a mystery known only to the dead and the dying. Like a dream or a near-death experience,
the qualities of one’s postmortem existence may be unique to every individual. They may
even resemble one or more religious interpretations of the afterlife.
However, there is little concrete knowledge we can draw from these fleeting visions beyond the grave.
As curious as we are to discover what awaits us in the great beyond, our understanding of life
after death may always be limited to our faith, our spirituality, and our collective imagination.