I used to think serifs were just decorative fluff.
Then I spent three months staring at the letter ‘T’ in Garamond, trying to understand why that tiny curved transition between the serif and the vertical stem felt so—I don’t know—right. Turns out, those curves aren’t random at all. They’re called brackets, and they’re doing something pretty sophisticated: distributing visual weight so your eye doesn’t trip over sudden angles. The best type designers obsess over these transitions the way sculptors obsess over how marble meets shadow. Adrian Frutiger once said he spent weeks adjusting bracket curves in Univers because a too-sharp junction made readers unconsciously tense up. That’s not metaphor—eye-tracking studies from the University of Reading in 2018 showed that abrupt serif-to-stem connections cause microsaccades, tiny involuntary eye movements that slow reading speed by roughly 8-12 milliseconds per glyph. Multiply that across a novel and you’ve added minutes of fatigue.
The Geometry Nobody Taught You About in Design School
Here’s the thing: bracket curves aren’t circles or ellipses.
They’re Bézier curves, sure, but the control points sit in places that violate every instinct you’d have if you were just trying to “round a corner.” Matthew Carter told me once—well, not me specifically, but in a lecture I attended—that when he designed the brackets for Georgia, he positioned the curve’s apex slightly inside the theoretical join point. This creates what he called “optical tension,” a microscopic departure from mathematical perfection that somehow reads as more balanced to human vision. I’ve tried replicating this, and honestly? It’s maddening. Move the control point 0.5 units and the whole letter looks drunk. The Dutch type designer Fred Smeijers wrote in Counterpunch that Renaissance punchcutters intuited these curves by hand, no equations—just feel. They’d cut steel punches under magnification, adjusting the fillet between serif and stem until it “sang.” That’s the word he used. Sang.
What Happens When Brackets Fail and Why You Definately Notice
Bad brackets announce themselves.
Times New Roman—yes, the default font that shipped with every Windows PC—has notoriously clunky brackets on the lowercase ‘n’ and ‘m’. If you zoom to 400% and trace the curve where the serif meets the stem, you’ll find a weirdly flat spot, almost a facet, where the designer (Stanley Morison, working under brutal deadlines for The Times in 1931) just… gave up. This isn’t speculation—Morison’s own notes, archived at St Bride Library in London, include a sketch with the annotation “insufficient time for proper filleting.” That flat spot creates a visual “clunk,” a tiny moment where your eye stumbles. Most people never consciously see it, but subconsciously? You feel it. It’s why Times New Roman, despite being everywhere, scores lower in sustained reading comfort tests compared to fonts like Minion or Freight Text, which have obsessively refined brackets. Wait—maybe that’s too harsh. Times New Roman was designed for newsprint at 9-point size, where those brackets would blur into smoothness anyway.
The Surgical Precision Required to Make Something Look Effortless and Natural
Modern type design software lets you plot bracket curves with mathematical precision.
FontLab and Glyphs give you control-point coordinates down to thousandths of an em unit (an em is the square of the type size—roughly the width of a capital ‘M’, give or take). But here’s where it gets weird: the “best” bracket curve often isn’t the smoothest mathematical curve. Erik Spiekermann, who designed FF Meta, told a workshop audience in Berlin that he deliberately adds a microscopic “bump” to his brackets—a second-order discontinuity that’s invisible at text sizes but creates what he calls “energy.” I guess it makes sense. Curves that are too perfect read as sterile, digital. The human hand, even when cutting metal punches in 1540, had tremor. That tremor is information. Contemporary type designers sometimes use algorithms to add synthetic irregularity back into bracket curves—0.3% deviation from the ideal Bézier path, randomized per glyph instance. Adobe’s variable fonts use this trick; the brackets in their optical size axes subtly shift their curvature as you scale from 6-point to 72-point, maintaining that hand-cut feel.
There’s a reason why people still pay $400 for Hoefler Text.
Anyway, next time you’re reading a book and you feel that weird satisfaction when your eyes glide across a line—no stumbles, no friction—zoom in on a capital ‘E’ or lowercase ‘b’. Look at where the serif kisses the stem. That curve took someone three weeks to get right. And you’ll never unsee it.
