I once wrote in a caption that I am “more often confused than knowing.” And right now, as it happens, I’m genuinely confused about what to write for my first post.

My imaginary friend gave me a suggestion. (He’s actually just me, talkin’ to myself).

“Just write about certainty.”

Alright then. Let’s talk about certainty… or the lack thereof.

What is actually certain in this universe?

I’d probably answer that question with a faint smirk and say,

“Perhaps the only certainty in the universe is our perception of matter within space and time.”

Sounds a bit pretentious, doesn’t it? Like someone who spends too much time alone, imagining they’re some kind of deep philosopher.

But before I try to explain it, there’s one thing bugging me.

Who asked the question in the first place? Oh, right. Me.

If the very question of certainty was born from my own mind, then perhaps certainty isn’t something that exists “out there.” Maybe it’s just a byproduct of how I perceive the world.

We often feel that a leaf is certainly green. But is it really?

…The answer is: not necessarily.

If you search YouTube for “how color is processed by the brain?”, you’ll find educational content explaining photoreceptors in the retina. Essentially, these cells convert light wavelengths into electrical signals, which the brain then interprets as a mental experience we call color.

We label the 540 nm wavelength as “green” simply because we’ve all agreed to do so.

Our photoreceptors, specifically the M-cones (medium-wavelength cones), are sensitive to the 540-570 nm range. The brain compares activation patterns: If the S-cones are active, it’s blue; M-cones, it’s green; and L-cones, it’s red.

So, when 540 nm light hits the eye, the M-cones fire more intensely. The brain concludes: This is green.

In reality, color as a property of light isn’t “certain.” It is a neural interpretation unique to Homo sapiens.

Is the leaf green? The answer depends entirely on who’s looking.

If “green” is just a mental label, what’s left outside of our heads?

Maybe the universe never truly painted matter with colors. Maybe there are only electromagnetic wavelengths.

Would those numbers still exist even if we weren’t there to see them?

But whatever that certainty is, the labels cooked up by our nervous system are important—mostly so we don’t go crashing into trees while walking.

So, when I ask what is certain in the universe, am I actually looking for certainty… or am I just looking for a label that feels certain?