Observable

Every construct needs a stand-in you can actually see in a log or a form. This slot names that visible event precisely, so any two people can point at the same row and say yes or no. The arithmetic comes later.

Every construct needs a stand-in you can actually see in a log or a form. This slot names that visible event precisely, so any two people can point at the same row and say yes or no. The arithmetic comes later.

Example

In the activation fight, you write: observable equals a login event by the same account ID between 24 and 168 hours after signup, recorded in the auth table. Not "engaged user," not "came back." A timestamped row anyone can pull.