How do I know if a change in me will stick?
The honest answer is that you probably cannot tell from the inside, and that is not a personal failing. It is a structural problem with how memory works.
Why You Can't See It
When you change, your memory quietly edits the earlier version of you to match who you are now. Ask yourself what you were like three years ago and you will almost certainly underestimate how different the thinking actually was. This is called memory reconsolidation, and it means the very tool you are using to measure change is also erasing the baseline. You feel like you have always been roughly this person, which makes genuine movement invisible and backsliding feel larger than it is. The change happened, but the evidence it happened against is gone.
What Actually Shifts vs. What Doesn't
Behavior under pressure is the most reliable signal. It is easy to act differently when things are comfortable. The question is what you do in the same situation that used to knock you sideways. If you handled that situation differently last month, and differently again this month, that pattern is more meaningful than any single moment of clarity. What tends not to shift quickly is the underlying sensitivity, the thing that makes certain situations hard in the first place. That sensitivity often stays, but your response to it changes, which is functionally the same result and takes longer to notice because you are still getting activated, just recovering faster or choosing differently once you are.
The Problem with Feelings of Change
Feeling changed is one of the weakest predictors of lasting change. That feeling is loudest right after a hard conversation, a difficult book, a period of real effort. It fades, and when it fades people often conclude the change was temporary, when actually the change is now just operating quietly in the background where it belongs. The flip side is also true: people who have genuinely changed often feel suspicious of it, like they are waiting for their old self to reassert itself. Neither the confidence nor the doubt tells you much. What tells you something is the record of decisions made in specific, comparable situations over time.
One Thing That Actually Helps
Write something down now, with a date on it. Not a goal, not a resolution. A description of how you actually think right now, what bothers you, what you want, what you avoid, what you tell yourself when things go wrong. Seal it. Look at it in six months. The gap between the two versions, if you resist the urge to edit either one, is the only honest measure you have access to. Memory will not do this for you because it cannot hold two versions at once. A dated record can. LUX starts with six open questions that take about eight minutes and gives you one word plus a card dated the day you begin. From there, the record grows as you add to it and compresses into readings that describe who you are now, not who you were when you started. The earlier version stays, which is the one thing memory will not do for you.
When this runs your life, it usually traces to one underlying pattern. For this, it is most often the Keeper rhythm, the thing under the behavior.
Where to take this
You cannot check this against memory, because memory quietly edits the earlier version to agree with the current one. The drift checker takes something you wrote a while back and something you wrote recently and names what actually moved and what held. Free, no signup, and nothing you paste is kept.