We talk a lot about openness, sharing information, publishing. But what about if you want to do the opposite. Keep something secret.
To keep secrets we could learn some easy-to-use principles from the military.
This is an excerpt from an instruction book for how to classify information - used within Swedish military and others:
"Våra försvarsförberedelser är i vissa fall svåra, i andra lätta, att dölja för omvärlden. Det är svårt att dölja våra resursers existens, något lättare att dölja resursernas egenskaper och tillstånd och lättast att dölja våra avsikter beträffande resursernas utnyttjande."
(RISK 1990 - Riktlinjer för sekretessbedömning inom försvarsmakten, M7745-705003)
The text says that it is hard to hide the existence of something. A bit easier to hide performance and status and easiest to hide the purpose or objective.
Presence, Performance, Purpose = 3P as guide for how to keep secret.
Example 1. It is hard to hide that your country develop a new bomber - B8. You can hide the fact in the early phase perhaps. When the "enemy" has discovered your bomber - you can still hide performance and status. How many bombs can it carry? What sort? What range can it operate within? But even those things will be known soon. So, now you can still hide its purpose or objective. How are you going to use the bomber? And what country will you attack first...
Example 2. You have a secret lover. Your husband will find out eventually. Denying the existence would then be silly. But performance and status, such as hair-color, sexual performance, how often you meet the lover can still be hidden. After a while even thse things will be known. But your last secret - purpose/objective - will be the hardest to figure out for your husband. Will you leave husband for lover? What is your plan with the lover? Will you get another lover?
If you want to keep something secret - consider the 3P - Presence, Performance and Purpose. Be prepared that the secret will be known by others in that order.
Do not struggle to much hiding its Presence. Hide the Performance instead. But most important - never give away Purpose!