Sorry- I overlooked your question. I did not mean to seem to ignore it.
“Sin of existence” is the ‘guilt’ which necessarily pertains to human existence. That is, not a personal guilt, but like Original Sin. Yes, the Original Sin is removed in baptism, but its consequences (suffering, death, the tendency to personal sin) all continue.
This idea, of some kind of original sin, is retained also by otherwise atheistic philosophers like Sartre and Heidegger. I suppose that what it comes down to is were born into a particular narrative and human state which is imperfect, and our very selves are born with various imperfections- as if, to paraphrase the Psalm, we are born into guilt. Not that we have done anything personally wrong…
It’s exactly the same reality as Original Sin.
The reality of Original Sin is an action.
It is impossible that a symbol or an explanation is exactly the same reality as an individual human action in a different time and space. Even the individual physical brain is not interchangeable with the individual action of another individual human living and dying in the past.
A human person, created in the image of God (as Professor Adam knew) is an unique being at once corporeal and spiritual. (Information source.
CCC 362-366)
You are correct that the consequences of the one and only Original Sin are suffering, [bodily] death, and the tendency to personal sin. Because of the unique composition of human nature, the whole human nature suffered the effects of Adam’s free choice to shatter humanity’s friendship state with the Creator.
Guilt is usually described as a personal emotion of varying degrees. Guilt does pertain to human existence, but it is not a separate existence, that is, guilt does not walk about talking on a cell phone. I exist. At least that is what I learned when looking in the mirror in space and time. I flat out refuse to be the existence of sin even though I have committed sins. My sins and the subsequent guilt may have affected my decomposing anatomy, but they are not the very same as my blood and guts, skin and bones existence.
What I see happening is that philosophers needed to explain inner guilt. Descartes gave philosophers the permission to separate the spiritual principle from the material principle. Over time, this separation continued its path eventually known as Cartesian extreme dualism. My ancient philosophy professor, not Professor Adam, demonstrated that some of the principles of Descartes eventually seeded Communism.
A few years ago, I read a wonderful paper by a British defender of the animal right to decent care and protection. He thought that the assumption that there was no spiritual principle (feelings) in an animal, would eventually lead to ignoring the inherent value or nature of animals. While animals do not have a rational spiritual soul the same as humans, they are highly sentient. And thus, they deserve our respect…something philosophically similar to the respect that humans deserve because of the union of soul and body. (Information source for human’s spiritual soul.
CCC 356-357;
CCC 364-366)
How all of the above relates to inner guilt is the faulty reasoning that inner guilt is somehow part of the body’s formal physical existence which is somehow separate from the body’s spiritual principle. This kind of separation leads away from the real action of the real Adam which affected human nature per se. It also leads to downplaying the role of God as Creator and eventually it dismisses both God and our need for understanding our own spirituality.
In other words, the short story is that Original Sin did not become our sin of existence, but it did affect our original relationship with God because in Adam was the whole humankind “as one body of one man.”
(Information source.
CCC 404; St. Thomas Aquinas,
De Malo 4, 1)
Over the centuries, the necessary existence of God moved away from its prominent position in human thinking. When we study the concepts of the first three chapters of Genesis, we discover that Professor Adam had no doubts about the existence of God. (Genesis 1:1) and thus his philosophy included human creature’s relationship with the Creator.
To truly understand human nature and its purpose on planet earth, one has to start at the beginning of human history.