Yes—this is an important distinction in Kierkegaard, because tungsind and despair (fortvivlelse) overlap but aren't the same thing.

Tungsind is usually translated as melancholy, heaviness of spirit, or dejection. Kierkegaard often uses it to describe a particular psychological or emotional condition. Despair, by contrast, is a deeper relation of the self to itself.

Tungsind

Tungsind literally has the sense of something like "heavy mind/spirit." Kierkegaard uses it for a state of profound melancholy, sadness, heaviness, and sometimes an inability to explain why one feels that way.

A person experiencing tungsind might essentially think:

"I am unbearably heavy, but I don't even know why."

The important point is that tungsind doesn't necessarily mean that the person has made some fundamentally wrong choice about themselves. It can be an affective condition—something one suffers from.

Kierkegaard's journals are particularly revealing here because he frequently describes his own melancholy in terms resembling tungsind.

Despair

Fortvivlelse, on the other hand, is much more specifically existential.

In The Sickness Unto Death, Kierkegaard defines despair through the self's relationship to itself. The question isn't simply:

"Am I sad?"

but:

"How do I relate to the person I am?"

Someone can therefore be miserable without being in despair in Kierkegaard's technical sense. Conversely, someone can be outwardly successful, happy, and functioning normally while nevertheless being in despair.

That's because despair can be hidden beneath ordinary life.

The difference in one sentence

You could put it roughly like this:

Tungsind is a heaviness one experiences; despair is a problematic way one's self relates to itself.

Or:

	Tungsind	Despair
Basic character	Melancholy/heaviness	Existential/spiritual condition
What it concerns	How one feels	How one is a self
Consciousness	Can be mysterious or inexplicable	Can be conscious or unconscious
Requires rejection of oneself?	No	In some form, yes
Can occur without the other?	Yes	Yes
Kierkegaard's concern	How to live with/understand the melancholy	Becoming a true self

There's also an important complication: Kierkegaard sometimes treats melancholy as something that can become intertwined with despair.

For example, suppose someone experiences profound tungsind. They may begin to think:

"This is simply who I am. I cannot change. I cannot become anything else."

At that point the melancholy can become bound up with a person's conception of themselves. The problem has moved from "I feel terrible" toward "I cannot—or will not—be the self that I am supposed to become."

That is much closer to Kierkegaard's fortvivlelse.

And this is why Kierkegaard's distinction is subtle

He doesn't simply say:

melancholy = psychological, despair = religious.

Rather, tungsind can be the felt experience, while despair describes the structure underneath the experience.

This is particularly interesting in Kierkegaard because he thought that trying to eliminate melancholy entirely could itself be a mistake. Some suffering can expose truths about oneself that distraction conceals. His concern was whether one relates to that suffering truthfully or uses it to become closed in upon oneself.

So a Kierkegaardian might distinguish:

"I am suffering from a terrible heaviness."
→ tungsind

from

"I cannot bear being the self that I am, and I cannot accept that I am dependent upon anything beyond myself."
→ despair

The second is much closer to what Kierkegaard means technically by fortvivlelse.

Søren Kierkegaard believed that anxiety is caused by human freedom and the overwhelming awareness of our own infinite possibilities. [1, 2]

In his 1844 book The Concept of Anxiety, the Danish philosopher explained that anxiety is fundamentally different from fear. While fear has a specific, tangible object (like a dangerous animal or a physical threat), anxiety has no specific object. Instead, it arises from nothingness—specifically, the blank canvas of what we are free to choose and become. [1, 2, 3]

Key Causes of Anxiety

The Dizziness of Freedom: Kierkegaard famously called anxiety the "dizziness of freedom". He compared it to a person standing on the edge of a tall cliff or building. When you look down, you feel fear of falling, but you also experience a terrifying dizziness (vertigo) because you realize you are entirely free to jump. Freedom opens up a dizzying array of paths, and the responsibility for choice rests solely on the individual. [1, 2]
The Human Duality: Humans are a synthesis of opposing states: finite and infinite, body and spirit, physical reality ("beast") and eternal possibility ("angel"). Anxiety is the tension that erupts when our spiritual, infinite side contemplates the limitations and choices of our earthly existence. [1, 2, 3]
The Reality of Choice and Possibility: Because we are conscious spiritual beings, we have the absolute capacity to choose our actions, make mistakes, and shape our own futures. The sheer boundlessness of this potential paralyzes us, creating an anxious weight before any action is even taken. [1, 2, 3]
The Attraction to What We Fear: Kierkegaard described anxiety as a "sympathetic antipathy"—a strange, paradoxical desire for the very thing we fear. We are simultaneously repelled by the unknown consequences of our freedom and magnetically drawn to exercise it. [1]

The Purpose of Anxiety

Kierkegaard did not view anxiety as a purely pathological disease to be cured, but rather as a profound wake-up call. Most people try to escape anxiety by blindly following the crowd or losing themselves in daily distractions. However, confronting anxiety forces us out of our unthinking state ("immediate existence") and thrusts us into self-awareness, personal responsibility, and spiritual growth. [1, 2, 3]