Dr Jack Parry 3 May 2026
keywords: Jaspers Existenz boundary situation Grenzsituationen positive suffering myelin chiasm accumulated condition becoming
Karl Jaspers published Reason and Existenz in 1935. It is a short book, five lectures delivered in Groningen, and it is one of the most demanding things in the philosophical literature, not because the prose is difficult but because what it is pointing at resists being looked at directly. Jaspers was trying to name the becoming of the authentic self, what he called Existenz with a capital E, and he knew that the moment you name it clearly you have already lost it, turned it into a concept, an object, a thing that can be pointed at and filed away. The book lives in that tension throughout.
Reading it for the first time, the recognition is immediate and unsettling. Jaspers is describing something the Myelin Mind has been trying to say in biological language, from a completely different direction, eighty years earlier, without any of the neuroscience that would later confirm him.
Existenz, for Jaspers, is not a property a person has. It is something a person becomes, and they become it only under specific conditions. Those conditions are the Grenzsituationen, the boundary situations: suffering, struggle, guilt, the confrontation with death, the encounter with what cannot be managed or predicted or thought through from a safe distance. These are the situations that cannot be entered from outside. They can only be lived through from within.
The boundary situation does not destroy the self. Or rather, it may destroy it, but if it does not, what emerges is a self of a different order than the one that entered. The Existenz that passes through the boundary situation is constituted by that passage. The self that avoids the boundary situation does not thereby preserve itself. It simply fails to become what it might have been.
Jaspers called this positive suffering. Not suffering as damage or deprivation, but suffering as the productive encounter with what exceeds the self’s current resources. The suffering that teaches nothing, because nothing was at stake in the encounter, leaves no trace. The suffering that constitutes, because the self was genuinely risked in the encounter, leaves the self different on the other side.
The Myelin Mind calls this activity-dependent myelination. Axonal firing under conditions of genuine resistance drives oligodendrocyte precursor cells to differentiate and wrap the axon in myelin. The productive struggle inscribes itself in the white matter. The encounter that costs something is the encounter that becomes the accumulated condition. Comfort does not myelinate. Ease does not myelinate. The boundary situation is the signal the myelination process was built to respond to.
Jaspers was describing myelination in 1935 in the language available to him, because the biology had not yet been named.
Existenz also requires encounter with another Existenz. The self cannot become authentic in isolation. What Jaspers calls genuine communication is not the exchange of information between two finished selves. It is the encounter in which both parties are changed by the meeting, in which neither arrives at the end of the conversation exactly as they entered it. The self is constituted through this kind of encounter, not through the accumulation of information but through the genuine risk of meeting something that the accumulated condition cannot reduce to what it already knows.
The Myelin Mind calls this the chiasm: the encounter between incoming signal and accumulated myelinated condition in which something is produced that neither party could have generated alone. The quality of the encounter, whether it demands a genuine response from the accumulated condition or merely confirms what was already known, determines whether the chiasm produces new inscription or merely rehearses the old one.
Every article on this site was produced through exactly this kind of encounter. The accumulated condition of thirty years of philosophical inquiry and biomedical animation practice met a stochastic system that pushed back, corrected, refused, and occasionally found a path the accumulated condition had not seen. The chiasm was productive because the encounter was genuine. Something emerged that neither party could have produced alone.
That is Jaspers’ genuine communication in biological form.
The hardest thing Jaspers says, and the thing most relevant to the Myelin Mind, is about objectification. Existenz cannot be made into an object without being falsified. The moment the living becoming of the self is turned into a scientific concept, a measurable variable, a thing that can be located and examined, it stops being Existenz and becomes a concept pointing at Existenz. The description is always one step removed from the living thing.
The Myelin Mind does not resolve this problem by ignoring it. It dissolves it from an unexpected direction.
The objectification is not something done to Existenz from outside by the scientist. The objectification is what myelination itself does. The chiasm, the living encounter between incoming signal and accumulated condition, inscribes itself in the white matter and thereby produces the persistence that makes future encounters possible. The living event becomes the accumulated structure. The encounter becomes the condition. This is not the scientist spatialising the living process. This is the organism doing it to itself, as the normal consequence of having an encounter at all.
The hard problem of consciousness asks how physical processes produce subjective experience. Jaspers’ formulation suggests a different question: what is the structure of the encounter that constitutes the self? The Myelin Mind answer is that the encounter is the chiasm, neither grey nor white matter but their living meeting, and the subjectivity of that encounter is not produced by the physical process but is the living meeting itself, before it has become the inscription that follows.
Existenz is the chiasm. Not what the chiasm produces. The chiasm in the act of occurring.
The myelinated condition is what the chiasm leaves behind: the accumulated objectification of a life of boundary situations, inscribed layer by layer in white matter, making each new encounter possible by providing the accumulated condition that will meet it. The self is the sum of its boundary situations, written in myelin, open to the next encounter that will rewrite it again.
Jaspers said we become ourselves through positive suffering. The biology says the same thing, in a different language, with different tools, pointing at the same room.
Further Reading
The primary text: Jaspers’ five Groningen lectures in which Existenz, the boundary situation, and genuine communication are developed as the proper objects of post-systematic philosophy: Jaspers K. Reason and Existenz. Noonday Press, 1955 (originally delivered as lectures in 1935)
Jaspers’ larger philosophical system, in which the boundary situation, positive suffering, and the conditions of authentic becoming receive their fullest treatment: Jaspers K. Philosophy. University of Chicago Press, 1969 (originally published 1932 as Philosophie, three volumes)
The foundational paper on activity-dependent myelination, confirming that genuine productive struggle is the biological signal that drives the inscription of encounter in white matter: Fields RD. A new mechanism of nervous system plasticity: activity-dependent myelination. Nat Rev Neurosci. 2015;16(12):756-67. DOI: 10.1038/nrn4023
The companion article on this site covering the methodology of moderated stochastic harnessing, in which the biological account of genuine communication is enacted in the production of the site itself: Harnessing the Stochastic Bull: On the Methodology of This Site — https://myelinmind.com/harnessing-the-stochastic-bull/
The companion article covering Deleuze’s three syntheses of time mapped onto the three biological modalities of myelin, the closest analogue in the site’s philosophical literature to the Jaspers argument made here: Deleuze Your Mind — https://myelinmind.com/deleuze-your-mind/
Jack Parry is a philosopher, polyglot, biomedical animator and cross-disciplinary eidetic researcher at Swinburne University of Technology. His research methodology employs moderated stochastic harnessing as a means of generating new knowledge across disciplinary boundaries. He is the author of The Myelin Mind: The Genesis of Meaning.