info.lifespan.dev/notes/2025/05/13/spans

What's a span?

OK, this is kind of important :-)

The unit of knowledge in Wikipedia is the article.

The unit of knowledge in Lifespan is the span.

A span is not a page with information in it.

It’s a thing with a URL that’s defined by dates.

A span is a period of time.

The dates can be precise to the day, month or year…

…so 12 March 1987, March 1987 or just 1987

Some spans have a start and an end, others just a start (because they’re ongoing).

It’s possible to know the end and not the beginning, of course.

We’ll ignore that for now.

There are different types of span.

You can have any type of span you like.

Any type of span you like, as long as it makes sense to add it to the system and isn’t just a duplicate of something else…

And so on…

Some types of span have sub-types.

The spans above are nouns. They’re the subjects and objects in sentences.

There’s a special type of span called a connection, which is where verbs come in.

Connections have three important things about them:

1. What type of connection they are
2. What their subject is
3. What their object is

There are rules that say which types of span can be connected by which types of connection.

(A place can’t be a member of a band)

Subject and objects make 3-word sentences with their connection, like this:

subject verb object

Things like

• person lived in place
• person member of band
• band created album

You can read a connection forwards or backwards.

• David Bowie lived in New York (forwards)

• New York home to David Bowie (backwards)

• Nirvana created Nevermind (forwards)
• Nevermind created by Nirvana (backwards)

It’s the same thing, just a different direction for the verb

The thing is, a connection is itself a span.

Which means it has a start and maybe an end.

So:

Something interesting here: 1721 is the start of the span, even if the label arrived 185 years later.