This is a post from Robin Sloan’s lab blog & notebook. You can visit the blog’s homepage, or learn more about me.

The trinary dream endures

October 19, 2025

Since the beginning, there has been an alter­na­tive vision for computing, not binary but trinary, also called ternary. (“Tri­nary” sounds so much better to me.)

Tri­nary didn’t make any headway in the 20th century; binary’s direct map­ping to the “on”/”off” states of elec­tric cur­rent was just too effective, or seductive; but remember that elec­tric cur­rent isn’t actually “on” or “off”. It has taken a ton of engi­neering to “simulate” those abstract states in real, phys­ical circuits, espe­cially as they have gotten smaller and smaller, down to the scale where quantum physics begins to have some inter­esting opin­ions about “open” and “closed”, “on” and “off”.

Tri­nary is philo­soph­i­cally appealing because the ground-floor vocab­u­lary isn’t “yes” and “no”, but rather: “yes”, “no”, and “maybe”. (That third state could alter­na­tively be “don’t care”.) It’s prob­ably a bit much to imagine that this archi­tec­tural dif­fer­ence could reach up through the layers of abstrac­tion and tend to pro­duce soft­ware with subtler, richer values … yet I do imagine it.

Tri­nary might still have its day. You can train a capable and super-efficient lan­guage model using weights of only -1, 0, and 1, and I believe many models in the future will use this architecture.

Viva la “maybe”!

P.S. I don’t say this explic­itly in Moonbound’s text, but I do lay out a few numeric clues, and here I will confirm, for the curious, that the com­puter sys­tems of the Anth at their apex were indeed trinary.

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