The error log

Everything in this course is ordinary except this. If you do one thing, do this.

#Why it works

Reading an explanation gives you recognition, not knowledge. You nod, it makes sense, and three weeks later you miss the same question in a different costume — because what you learned was that specific question, not the pattern underneath it.

The log forces you to name the pattern. Naming it is the learning.

#The format

Four columns. A spreadsheet, a notebook, whatever you'll actually keep.

Only the fourth column matters. The first three are bookkeeping. If the fourth column says "careless" or "silly mistake", you haven't done the work — those aren't reasons, they're a refusal to look. Every careless mistake has a mechanism: you read the first clause and stopped, you misread a sign, you answered the question you expected instead of the one asked.

#The taxonomy

After thirty entries, sort column four. Almost everyone finds their misses collapse into five or six recurring causes. Common ones:

• Answered the wrong question. Solved for x when it wanted x + 2. Found the purpose when it asked for the function.
• Stopped reading early. Picked the choice whose first half matched.
• Ignored a signal word. Missed a however, a not, an except.
• Overreached. Chose the stronger claim the evidence didn't carry.
• Rule not automatic. Knew the comma rule, took too long, got it wrong under pressure.
• Arithmetic. Sign error, dropped term, mis-transcribed.

Your five are your actual syllabus. Not the domain list — these.

#The re-do rule

Once a week, re-do every logged question from scratch. Cover your old answer and your note. Do it as though it were new.

A question you can now do cold comes off the list. A question you miss again goes to the top, and the note gets sharper. This is the mechanism — not the logging, the re-doing.

#A note on volume

Twenty questions properly logged beat two hundred done and forgotten. If you're doing so many questions that you can't log them, you're doing too many.