The receipt beats the memory

I keep my affairs in a collection of notes: on people, vehicles, contracts and ongoing matters. Each note holds the current state, meaning what is true now. It is fed from many sources: messages, emails, scanned receipts, summaries dictated in the evening.

Sooner or later two statements contradict each other. A date, an amount, a period of time. The obvious rule is that the newer statement replaces the older one. That rule is almost always wrong.

Why “written last” says nothing about quality

Information doesn’t arrive in the order in which things happened. A message from the afternoon is often recorded only after the evening dictation of the same day, although it was written earlier, closer to the event, and carries the exact wording. An invoice arrives by post days later, a bank statement weeks later.

“Recorded more recently” therefore means neither “said later” nor “better documented”. Anyone who decides by the order of recording will regularly let a vague summary overwrite a precise document.

The order of precedence

Instead, the better-documented statement wins. From strong to weak:

Document before memory. An invoice, bank statement, contract or measurement beats any account.
First source before summary. The message in which something was first said beats the later condensed version by the same person.
Wording before paraphrase. What can be quoted beats what someone made of it.
Specific before vague. “Since December” beats “since May at least”, “1,240.80 euros” beats “a good thousand”. Words like “about”, “at least” or “I think” mark the weaker version.

Only when two statements are equally strong, two documents or two original statements, does the newer one win. Then and only then is the order the right criterion. Conversely, old is not automatically better either. A new document beats any older memory.

The displaced version stays visible

When a statement is corrected, the old one doesn’t silently disappear. It stays as a short note below the new value, with its source and time. That way a later reader sees that there were two versions and why one of them won. Without that note, the next contradiction starts the whole clarification over again.

There are two mistakes to avoid. The first is silent overwriting. The second is its opposite: leaving both values side by side as equals, “May or December”. The current state has to make one statement. The alternative belongs in the note, not in the statement.

If the stronger statement shifts something material, an order of magnitude, a period, a risk, correcting the note is not enough. The decisions taken on the basis of the old statement must be reviewed too: deadlines, notices to third parties, priorities.

Memory doesn’t make a ledger entry

For one category the line is particularly firm: account movements. When I mention that I sold or transferred something, that is material for the note on the matter. It only reaches the account overview once the bank statement has been imported.

The reason: a transaction entered by hand has no origin and no reconciliation with the balance. On the next real import it collides as a duplicate or, worse, it looks checked when it isn’t. Every check on the account overview depends on each line coming from an import. Until then the overview lags behind the conversation. That is not an error, it is the normal state of affairs.

What the source doesn’t say isn’t filled in

The third variant of the problem is the most treacherous: a piece of information is missing, and it gets filled in from what seems plausible. The result reads like a fact but has no source.

An example from my own life: the notifications from a classified-ads site named the other party and the title of the listing, but not who was buying and who was selling. My notes nevertheless said it was my own listing and that the other party was the buyer. It was exactly the other way round. The mistake lasted three days, and every consideration that depended on it went in the wrong direction: who owes whom what, who proposes the appointment, which way the money flows.

The rule that follows: not stated means not claimed. Phrase it neutrally, mark the open question as open, and first check the sources that can actually answer it. Your own sent folder, the first message of the exchange or the direction of a payment settle the question more firmly than any prose.

The same applies to dates from dictation. Speech recognition mishears weekdays too, and if the misheard weekday happens to match the date, no calendar check will notice. For anything involving money, deadlines or health, a dictated date is therefore checked once against other traces from the same day before it counts as fact.

Why it matters

These errors are silent. An amount that is too low or a wrong period looks just as tidy in a note as a correct one. No automatic check finds it, because formally everything is in order. And decisions keep running on the weaker statement.

In the end, what counts is what can be documented. Before the tax office, before a court, towards a contracting party, and in an emergency towards someone who has to carry on my affairs without me. Memories are valuable, but they are the weakest source there is. My own included.