I need to keep a journal because as I change over time, my method of comprehending everything also changes, and some memories no longer fit my new system of comprehension.
If my memory were a computer database, then I would be adding rows to giant tables continuously, while changing the schema every time I find a better way of understanding things. Over time, some of those rows would become so far out of sync with the schema that no query would find them. Some of those practically forgotten rows would remain important, though. Keeping a journal is like copying vital data to an external store with a more stable schema. (The English language is more stable than my system of comprehension.)
I wonder if I ought to express that without a computer analogy. My kids need to learn it, but they certainly aren’t versed in all this jargon.