Heart

Heart

The human heart is a vital organ responsible for pumping blood throughout the body, supplying oxygen and nutrients to tissues while removing waste products such as carbon dioxide. The heart is a muscular, fist-sized organ located in the chest, between the lungs and behind the sternum (breastbone).

The human heart is comprised of four chambers: two upper chambers called atria (singular: atrium) and two lower chambers called ventricles. The right atrium receives deoxygenated blood from the body via the superior and inferior vena cava, while the left atrium collects oxygen-rich blood from the lungs through the pulmonary veins. Blood then flows from the atria to the ventricles through the atrioventricular valves (tricuspid valve on the right and mitral valve on the left). The ventricles pump blood out of the heart to the body and lungs, with the right ventricle sending deoxygenated blood to the lungs through the pulmonary artery, and the left ventricle pumping oxygenated blood to the rest of the body via the aorta.

The heart's pumping action is controlled by electrical signals produced by specialised cells within the heart tissue. The sinoatrial (SA) node, located in the right atrium, is known as the heart's natural pacemaker, as it generates electrical impulses that trigger the atria to contract. These impulses then travel to the atrioventricular (AV) node, which is situated between the atria and ventricles, and from there, the signals continue to the ventricles via the Bundle of His and Purkinje fibres, causing them to contract and pump blood.

The heart's function is supported by a complex network of blood vessels, including arteries, veins, and capillaries. Arteries transport oxygenated blood away from the heart (except the pulmonary artery, which carries deoxygenated blood to the lungs), whereas veins return deoxygenated blood to the heart (apart from the pulmonary veins, which bring oxygenated blood from the lungs). Capillaries are small, thin-walled blood vessels that facilitate the exchange of oxygen, nutrients, and waste products between blood and body tissues.

Literary Examples

Edgar Allan Poe's "The Tell-Tale Heart" (1843): In this short story, the narrator, driven by his overwhelming guilt, becomes obsessed with the sound of the beating heart of the old man he has murdered. The relentless thumping serves as a metaphor for the narrator's conscience, as well as the heart's association with guilt, fear, and the darker aspects of human nature.

Mary Shelley's "Frankenstein" (1818): In this classic horror novel, the scientist Victor Frankenstein assembles a creature from body parts, including a heart, taken from various corpses. The heart, along with the other organs, is used to create new life, highlighting the literal importance of the heart as an essential organ for sustaining life.

H. G. Wells' "The Island of Doctor Moreau" (1896): The protagonist, Edward Prendick, finds himself stranded on an island where the mysterious Dr. Moreau conducts gruesome experiments, creating hybrid creatures by grafting animal organs, including hearts, onto human bodies. The literal heart appears as an element of the doctor's macabre work.

Clive Barker's "The Hellbound Heart" (1986): In this horror novella, the character Frank Cotton seeks ultimate pleasure by summoning the Cenobites, who are otherworldly beings that blur the lines between pain and pleasure. At one point, Frank is skinned alive, and his heart is exposed as part of his gruesome punishment.

Cormac McCarthy's "The Road" (2006): In this post-apocalyptic novel, the world has been destroyed by an unspecified catastrophe, and the remaining survivors struggle to stay alive. One harrowing scene involves the discovery of a group of people who have been captured and are being cannibalised. The heart is mentioned as one of the organs being consumed, underscoring the brutality and desperation of this dystopian world.

In Religion

In various religious traditions, the human heart has held both literal and symbolic significance. Here are a few examples:

Christianity: In Christian iconography, the Sacred Heart of Jesus represents Christ's divine love for humanity. The heart is often depicted as a flaming heart surrounded by a crown of thorns, pierced by a lance, and bleeding. While this symbolism is not a literal representation of the human heart, it does hold a central place in Christian devotion and spirituality.

Ancient Egyptian religion: The ancient Egyptians believed that the heart was the seat of the soul and the source of emotions, intellect, and morality. During the mummification process, the heart was often left within the body, as it was thought to be necessary for the deceased to be judged in the afterlife. In the 'weighing of the heart' ceremony, the heart was weighed against the feather of Ma'at, the goddess of truth and justice. If the heart was lighter than the feather, the deceased would be granted passage into the afterlife.

Hinduism: Although the heart is not explicitly referred to in a literal sense, it is considered the abode of the divine Self (Atman) and is often associated with the spiritual heart or the heart centre (Anahata chakra). The Anahata chakra is said to be the seat of love, compassion, and emotional well-being and is one of the seven primary energy centres in the human body.

Buddhism: In some Buddhist traditions, the heart is believed to be the seat of consciousness and spiritual insight. The "Heart Sutra" is a famous Mahayana Buddhist text that explores the nature of reality and the cultivation of wisdom and compassion. While the heart is not discussed in a literal sense, the sutra's title symbolises the core teachings of Buddhism and their profound impact on the practitioner's heart and mind.

Aztec religion: The Aztecs practiced human sacrifice as a way to appease their gods and ensure the continuation of the world. They believed that the heart was a powerful and vital offering, as it was considered the most important organ and the seat of life. During sacrificial rituals, the heart would be removed from the victim and offered to the gods.

In various religious contexts, the human heart can hold both literal and symbolic significance, often representing the essence of life, the seat of emotions, or the dwelling place of the divine.

Heart as Metaphor

The heart has been a powerful and enduring metaphor for emotion across cultures and throughout history. It is often used to represent love, passion, courage, and other emotions. Here are some examples of the heart as a metaphor for emotion in literature, proverbs, and idioms.

Emily Brontë's "Wuthering Heights" (1847): This novel explores the complex and tumultuous relationship between Heathcliff and Catherine Earnshaw, showcasing the heart's role in strong, passionate emotions, and the destructive consequences of obsession and unrequited love.

Charles Dickens' "Great Expectations" (1861): The protagonist, Pip, undergoes a transformation of the heart throughout the novel. Initially yearning for wealth and social status, Pip learns the value of genuine human connection and the importance of the heart's capacity for love, empathy, and forgiveness.

Jane Austen's "Pride and Prejudice" (1813): In this romantic novel, the characters of Elizabeth Bennet and Fitzwilliam Darcy overcome their initial prejudices and misconceptions about each other, eventually falling in love. This classic tale underscores the heart's role in human relationships and the triumph of love over preconceived notions.

F. Scott Fitzgerald's "The Great Gatsby" (1925): The protagonist, Jay Gatsby, is driven by his desire to win the heart of his long-lost love, Daisy Buchanan. His pursuit of wealth, status, and a grandiose lifestyle to impress her ultimately leads to his tragic downfall, illustrating the heart's vulnerability and the dangers of misguided desires.

Romeo and Juliet

"Romeo and Juliet" is a tragic play written by William Shakespeare. It tells the story of two young lovers from feuding families in Verona, Italy, who fall in love at first sight and are determined to be together despite the deep-rooted animosity between their families, the Montagues and the Capulets.

The play begins with a street brawl between the two families, which draws the attention of Prince Escalus, who declares that any future violence between the families will be met with severe consequences. Amidst this tension, Romeo Montague attends a masquerade ball held by the Capulet family, where he meets and falls in love with Juliet Capulet. The two exchange vows of love and, unbeknownst to their families, marry in secret with the help of Friar Laurence.

As the story unfolds, Romeo becomes involved in a fight with Tybalt, Juliet's cousin, who kills Romeo's friend Mercutio. In retaliation, Romeo kills Tybalt, resulting in his banishment from Verona. Meanwhile, Juliet's parents, unaware of her marriage to Romeo, arrange for her to marry Paris, a wealthy nobleman.

Desperate to avoid this marriage, Juliet seeks the help of Friar Laurence, who devises a plan for her to fake her death using a sleeping potion. The plan is for Romeo to learn of the ruse, retrieve Juliet from her tomb, and flee together. However, a miscommunication leads Romeo to believe that Juliet is truly dead. In grief, he acquires poison and takes it at Juliet's tomb.

When Juliet awakens to find Romeo dead beside her, she chooses to take her own life by stabbing herself with Romeo's dagger. The deaths of their children ultimately bring the Montagues and Capulets together in shared grief, and the families reconcile, ending their long-standing feud. The tragic story of Romeo and Juliet serves as a cautionary tale about the destructive consequences of hatred and the transformative power of love.

Idioms

"A heart of gold": This popular idiom describes someone who is genuinely kind, compassionate, and generous. The metaphor of the heart suggests that these qualities are intrinsic to the person's nature.

"Heart of stone": This phrase is used to describe someone who is perceived as cold, unfeeling, or lacking empathy. The metaphor of a stone heart implies that the person is incapable of experiencing or expressing deep emotions.

"Wear one's heart on one's sleeve": This idiom means to openly display one's emotions or make one's feelings easily discernible. The heart is used as a metaphor to convey the idea that one's emotions are readily visible and accessible.

"The heart swells with pride": This expression conveys the feeling of great pride and accomplishment, with the heart metaphorically swelling due to the intense emotion experienced.

"Follow your heart": This popular saying encourages individuals to listen to their emotions and inner feelings when making decisions or pursuing their passions. The heart, as a metaphor, represents one's true desires and emotional instincts.

"A heavy heart": This phrase describes the feeling of sadness, grief, or despair weighing down one's emotions. The heart metaphorically carries the burden of these emotions, making it feel heavy and oppressive.

Heart and soul: Fully committed or deeply involved in something, putting all of one's energy and passion into a task or endeavour.

To have a change of heart: To change one's mind, opinion, or feelings about something, often after considering new information or having a new experience.

To take heart: To gain courage, confidence, or hope in a challenging or difficult situation.

To lose heart: To become discouraged, disheartened, or lose confidence in the face of adversity or setbacks.

To have one's heart set on something: To be determined to achieve or obtain something, having a strong desire or ambition to reach a specific goal.

To have one's heart in one's mouth: To experience extreme anxiety, fear, or nervousness, typically in anticipation of a significant event or outcome.

To know something by heart: To have complete knowledge or mastery of something, often through memorisation or repeated practice.

To have a heart-to-heart: To engage in a sincere, open, and honest conversation with someone, often discussing one's feelings, emotions, or personal matters.

To have a soft spot in one's heart for someone or something: To have a deep affection, fondness, or weakness for someone or something, often in a sentimental or nostalgic way.

To warm the cockles of one's heart: To provide a feeling of happiness, contentment, or satisfaction, often in response to an emotionally touching or heartwarming event.

A heart of glass: To describe someone who is emotionally fragile or easily hurt, suggesting that their heart is as delicate and breakable as glass.

To pour one's heart out: To openly express one's deepest thoughts, feelings, and emotions, typically in a conversation with someone else.

To have a big heart: To be kind, caring, and generous, often going out of one's way to help others or show empathy and understanding.

To give someone a piece of one's heart: To express strong feelings, opinions, or criticisms to someone, often in an emotional or passionate manner.

To have a heart of iron: To describe someone who is strong-willed, determined, and unyielding in their beliefs or decisions, suggesting that their heart is as steadfast as iron.

To strike at the heart of something: To address or target the core issue, central problem, or essential aspect of a particular matter or situation.

To eat one's heart out: To experience jealousy, envy, or regret, often in response to someone else's success, happiness, or achievements.

To have a heart of oak: To be strong, courageous, and dependable, often in the face of adversity or challenges, suggesting that one's heart is as sturdy and resilient as oak.

To have one's heart in the right place: To have good intentions or a sincere desire to do what is right or helpful, even if the outcome or execution is not perfect.

Close to one's heart: Something that is deeply important, cherished, or valued by an individual, often due to personal or emotional connections.

To steal someone's heart: To capture someone's affection or admiration, often unexpectedly or with great charm and charisma.

To have a heart of ice: To describe someone who is cold, unfeeling, or lacking empathy, suggesting that their heart is as unresponsive as ice.

Young at heart: To have a youthful, lively, or energetic spirit, regardless of one's actual age, often characterised by a positive outlook and enthusiasm for life.

To win someone's heart: To gain someone's love, admiration, or loyalty, often through acts of kindness, generosity, or understanding.

To have a lion's heart: To be brave, courageous, or fearless, often in the face of adversity or danger, suggesting that one's heart is as bold and strong as a lion's.

To break someone's heart: To cause someone deep emotional pain or sadness, often as a result of ending a relationship, betraying trust, or disappointing them in some way.

To have a heart of gold: To be genuinely kind, compassionate, and generous, often going above and beyond to help others or make a positive impact on their lives.

To cross one's heart: To make a sincere promise or pledge, often while making the sign of a cross over one's heart as a gesture of commitment and honesty.

To have a change of heart: To experience a shift in one's feelings, opinions, or intentions, often after careful reflection or a new perspective on a situation.

To sink one's heart: To cause someone to feel great disappointment, sadness, or despair, often as a result of an unexpected setback or failure.