My favorite teacher

My favorite teacher wasn’t a very popular guy. He was confident, had strong opinions, and didn’t exactly teach like the other teachers.

He was our history & sociology teacher in 12th and 13th grade and he made us summarize. He made us summarize everything. Through summaries, he taught.

As a class, we would read a page in our history books about the Ems Dispatch in 1870 and he’d ask us: what does this text say, in three sentences?

Someone would raise their hand and try to summarize what we had just read, in three sentences. Sometimes it would be three sentences, sometimes not quite, and very often our teacher would say: no, that’s not what the text says, here’s what it says.

Then he would say three very clear and grammatically flawless sentences that perfectly summarized what the text said. You couldn’t help yourself and think that, god damn, this is exactly what the text said.

We would have to summarize newspaper articles in three sentences, summarize a letter in five sentences, summarize what we just heard in a radio recording in four sentences. He made us read the newspaper every day and ask us, every week, to summarize what had happened in the previous week: why did minister so-and-so step down, in three sentences?

We would struggle to get three sentences out, fighting grammar, memory, and understanding. He’d nail it every time.

He taught us that you can summarize anything, in whatever length you want. He could summarize the Cold War in two sentences. A new law around unemployment benefits and social security? Four sentences. Bismarck’s forced resignation and all the political maneuvering that proceeded it? Three.

Anything, he taught us, can be summarized in one, two, three, four, five sentences, but you need to know what you’re talking about and think clearly. Whenever someone would fail to summarize something, he’d say: “you’re not thinking clearly.”

Summarizing is thinking clearly.

What do you keep in a three-sentence summary and what do you leave out in the two-sentence version?

You can’t answer that without having thought deeply through a topic. Event by event, fact by fact, you have to extract what’s essential, skipping what’s merely a detail, always paying attention to causality and other forms of relationship between events and facts.

A way of thinking is what he taught me.

Often, when I write, I start with bullet points: what are the three things that I want to say? Then I flesh out the rest.

To test my knowledge of something, I ask myself: what’s being proposed in this RFC? In two sentences. Three sentences.

Or: wait, what did we just decide in this meeting? Two sentences. What does this code do? In one sentence? Two? Three? Do I know this code well enough to summarize it in different lengths?

I also flip it around and test by summarizing: can I summarize what I just wrote in three sentences? Or, as it often turns out, can I not because there’s no real structure to it and it’s trying to say too many different things without any order at all?

This code, this file, this method - what does it do? What’s its job - in one sentence, two, three? Turns out I can’t go lower than eight sentences because it does eight different things - maybe it’s time to rethink the code.

It’s been nearly twenty years and I very often think of the summaries we had to do, how our teacher shook his head, said “no, that’s not what it says”, and how right he was.