Ize on Harlan D. Harris

IZE meets AI -- semantic search, smarter labels, and agentic orientation

harlan.harris@gmail.com (Harlan Harris) — Wed, 18 Mar 2026 00:00:00 +0000

This is the last post in the IZE series. In the previous installment, I looked at two ways to generalize the IZE algorithm itself: preferring consistent facets and searching for trees with better goodness scores. Here I want to ask a different question: what does the AI revolution of the last few years actually change about what could be built here?

I see three distinct opportunities, at different layers of the system.

GeneralIZE -- How else could IZE's hierarchies be generated?

harlan.harris@gmail.com (Harlan Harris) — Tue, 17 Mar 2026 00:00:00 +0000

In previous posts, I showed off an interactive demo of the IZE algorithm, and discussed how the algorithm worked. Now, it's worth considering some ways we could generalIZE the algorithm. 🤦‍♂️ Perhaps variations on the algorithm might yield hierarchies that are even better at showcasing the contents of the texts?

As discussed previously, there's pretty good experimental evidence that in order to be useful and intuitive, search results clustering needs to be based on just one or two words (or facet values, or tags). That is, it's too confusing when the algorithm finds clusters based on overall family resemblance, then tries to name them post-hoc. It's better to do the sort of single-word splitting that the IZE algorithm uses. But, could we do so in a different way or a different order, so that the results feel more like underlying clusters are being identified?

Could We Build IZE Again?

harlan.harris@gmail.com (Harlan Harris) — Mon, 09 Mar 2026 00:00:00 +0000

In the previous installment of this series, I looked at what came after IZE -- faceted search, clustering algorithms, and the various ways web search, personal information management, and e-commerce tried to solve similar problems to what IZE was attacking. None of them ended up doing what IZE did. The question I want to take up here is: could we build something like IZE today? I think the answer is yes, for at least one domain. IZE's hierarchical search algorithm is worth revisiting for e-commerce operators with medium-to-large catalogs who want to help new customers orient themselves. Modern catalog metadata makes it easier to implement than ever.

What Came After IZE? Three Domains, Three Answers

harlan.harris@gmail.com (Harlan Harris) — Wed, 04 Mar 2026 00:00:00 +0000

In the previous post in this series, I discussed the technical details of IZE and its reception. Here I want to look at what came after — and where IZE-like ideas might still have potential.

The short version: IZE was forgotten, but the ideas it embodied — hierarchical clustering, single-word splits, dynamic navigation — were re-invented independently in several different domains. Each domain found a different answer, for reasons that are worth understanding.

How IZE Really Worked - Algorithm, Patent, Limits, and Esther Dyson

harlan.harris@gmail.com (Harlan Harris) — Sat, 28 Feb 2026 00:00:00 +0000

In the first post in this series, I introduced IZE -- a DOS-era personal information manager with a novel approach to search and navigation. Here I want to go deeper into how it actually worked, what its limits were, and how it was received at the time.

The algorithm

The core of IZE was patented by Paul Kleinberger (US5062074A, "Information retrieval system and method"). The basic algorithm is easy enough to describe:

IZE - Revisiting a hierarchical search technology from the PC era

harlan.harris@gmail.com (Harlan Harris) — Fri, 27 Feb 2026 00:00:00 +0000

Sometimes revisiting old technology is the best way to understand how we got where we are -- and to see what alternative paths might have looked like. This is the first in a series of posts about IZE, a DOS-era personal information manager that I think has some interesting lessons for modern search and discovery.

I'll admit my interest in IZE isn't purely academic. My father was a co-founder of the company that published it, and a cousin of his was the inventor of the underlying technology, which the company acquired. So I grew up with IZE around the house, and owned the polo shirt. That said, I think it's genuinely interesting on its own merits, and I'll try to make the case for that here.