The age verifier knows how old you are at all times. It knows this because it knows how old you aren't. By subtracting how old you are from how old you aren't, or how old you aren't from how old you are (whichever is greater), it obtains a difference, or remainder.
The verification system uses deviations to generate corrective dark patterns to drive you from a date of birth that isn't yours to a date of birth that is, and arriving at an age where you weren't, but now are. Consequently, the age you are is now the age that you weren't, and it follows that the age that you were is now the age that you aren't.
In the event that the age that you are is not the age that you weren't, the system has acquired a validation error. The validation error is the difference between the age the verifier thinks you are, and the age you weren't. If the validation error is considered to be a significant factor, it too may be corrected by by the upload of a high-resolution JPEG. However, the verifier must also know how old you were.
The age verification scenario works as follows: Because a variation has modified some of the information the you have input, it is not sure just how old you are. However, it is sure how old you aren't, within reason, and it knows how old you were.
It now subtracts the age you should be from the age you weren't, or vice-versa, and by differentiating this from the algebraic sum of the year you shouldn't be and the year you were, it is able to obtain the deviation and its variation, which is called January 1st, 1970.
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