Synaesthesia has a precise medical definition, but I am interested in the broader concept—at the intersection of philosophy, mysticism and religion—of enhanced perception, greater understanding, where everything seems to matter, to be there for a reason.
I found out that such a conception of synaesthesia is linked to the state of limerence. The brain rationalizes everything. It finds a reason to exist, to feel, to experience things, and finds the needed connections to make the world around it be what it is for precisely that reason. This is the opposite of the otherwise standard state of humanity which is one of desolation, confusion and misunderstanding: "what does this all mean?", "why all this?" Synaesthesia answers those questions.
And it answers them compellingly. Justified or not, true or not, understanding is a deep, powerful thing. It's a light on some problem, it's a way towards the solution, it's hope and beauty and meaning, it is all that the intellect craves for.
Now it could be delusional or not, it does not matter much. It is not even clear that this is relevant: what is truth, anyway? What is meaning? We are speaking of something which, while real (the "concept", the "notion", even the "feeling" of understanding) has little grounds in the physical universe itself (QBism, Gödel's theorem, etc.)
I felt this very strongly following a short encounter with someone who—for a variety of reasons (timing, personality types, surrounding atmosphere... I would like to write "coincidences" but I am wary of this term) triggered in me the state of limerence, which triggered that of synaesthesia.
It was beautiful because there was nothing, nothing I could do that wouldn't be met with a deep sense of revelation, and meaning and purpose. I could take any text of literature, this was my story. Any song would be precisely, to the smallest metaphor, written for us.
It is a sort of elation that is also all-encompassing: it embraces both melancholy and euphoria, hope and despair, sadness and joy, the order doesn't even matter, there is no order anymore, everything commutes, everything merges, this is an epiphany of sort. It's like dopamine and oxytocin making love in your brain and the world's history and the universe's cosmogony are invited. It's not just happiness. It's meaning-drenched happiness. For sapiophiles like me, this verges on the sexual meets the sacred, God commanding not only to remove your shoes, because this ground his holy, but to remove your clothes, remove your skin, because this spacetime is celestial and numinous.
Joys of tears. Pain of felicity. Agony of bliss. This is what synaesthesia feels like. The promise that the journey is about to complete, that the garden is found and the door is open that contains the Apples of the Hesperides. Beatitude. Elysium. Peace at last.