Explanation of a Jurisprudential Maxim: Anything in which estimation is claimed by number, manner, or size requires evidence, otherwise it is arbitrary without evidence, with mention of examples

The Shaykh : This is a beneficial jurisprudential maxim: "Anything in which estimation is claimed by number, manner, or size requires evidence, otherwise it is arbitrary without evidence" This will benefit you in every place. For example, if someone asks you, "What is the minimum duration of menstruation?" meaning, what is the minimum time that counts as menstruation? If you say one day and one night, we would ask you, "What is the evidence?" This is a woman who experienced menstruation for the first time and it lasted five days before she became pure. She says the minimum considered menstruation is one and a half days, and anything more than one and a half days up to five days is not menstruation. Who said this? The period between two menstruations is thirteen days. This is an estimation that requires evidence, does it not? So, what is the evidence that the minimum period between two menstruations is thirteen days? Who said the minimum is thirteen days? Bring the evidence. It may be that for some women, the period between two menstruations is ten days. It has actually happened that some women's menstruations coincide, so they do not menstruate for three months, and when they do menstruate, it lasts twenty days or more; it accumulates. Similarly, some women have a period of ten days between menstruations, but the duration of menstruation is less than five days, and natures differ. In any case, I am giving you this maxim: "Whoever claims something estimated in number, manner, or size, what is required of him? He requires evidence" So, we say that the span of a handbreadth for placing the feet in prostration requires evidence. As for the opening, a person might say the evidence is the absence of evidence, but the original nature is for the feet to be spread apart as the knees are spread apart.