Three filters are enough to determine if a relationship is sustainable, and they are applied in a specific order: pace, money, and disagreement. The first filter becomes apparent in three weeks, the second in three months, and the third with the first real conflict. A relationship that passes all three filters deserves time; a relationship that fails at the first filter never reached the second in the observed cases. This framework exists to prevent discovering after two years what was evident after three weeks.
A woman who has been an arbitrator for 20 years can read a balance sheet in 4 minutes and spot a cash flow anomaly before the end of the first page. The same analysis applied to a relationship takes years—because no one has ever laid out the lines to look at.
Here they are, in the order in which they inquired.
FILTER 1 — THE RHYTHM · can be read in 3 weeks
Rhythm is the frequency of initiatives, and nothing else. Who proposes, who confirms, who moves, who cancels.
Over 21 days, the tally is contained on a single line: the number of proposals made by each side. A ratio of 8 to 2 at the beginning of a relationship does not correct itself by month 4; it worsens—because the one who makes few proposals has already learned that they don't need to make any.
This is the least commented-on and most predictive filter. It takes 3 weeks to set up and prevents problems for the next 3 years.
FILTER 2 — MONEY · can be read in 3 months
Money isn't measured by the amount spent; it's measured by how the issue is addressed. Four configurations emerge after three months: the one who avoids the subject, the one who counts aloud, the one who compensates, and the one who decides without making a big deal out of it.
The 4th configuration is the only one that holds up in the long term, and it can be identified by a unique sign: the question of who pays never takes more than 4 seconds.
This filter is crucial for a woman who earns more. It's not about measuring financial capacity—it's about measuring whether the imbalance produces calm or accounting.
FILTER 3 — DISAGREEMENT · can be read in the first real conflict
The first serious disagreement occurs between the 4th and 8th month, and it provides more information in one evening than the previous 7 months.
Three approaches are possible, and only one fosters a relationship of equals. The first is to give in immediately to end the dispute—the disagreement will return unchanged three months later. The second is to turn the disagreement into a lawsuit and dredge up past events—the relationship will become a permanent dispute. The third is to hold their ground, listen to the opposing viewpoint, and agree to shift it slightly—this is the only approach that will sustain the relationship over time.
This filter cannot be artificially created. It appears on its own, and you simply need to look at it instead of holding your breath while swimming through it.
What the framework changes, in concrete terms
Without a framework, the reading is done retrospectively — after 2 years, with added sorrow and a conclusion that came too late to be useful.
With this framework, the reading progresses gradually: 3 weeks, 3 months, 1st conflict. 3 observations, 3 decisions, each made with the information available at the time it matters.
One Sunday in June, a terrace in the late afternoon, two drinks, and a frank disagreement on an important subject—acknowledged, listened to, shifted a notch, then closed again before dessert. Nothing spectacular to report the next day, and a relationship that had just passed its third filter.
Read next: dare to be ambitious · recognizing the right partner · concrete signs of a lasting relationship
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