<P> Since the Book of Genesis refers to young goats by the Hebrew phrase g'di izim, but the prohibition against boiling a kid...only uses the term g'di (גדי). Rashi, one of the most prominent talmudic commentators, argued that the term g'di must actually have a more general meaning, including calves and lambs, in addition to young goats . Rashi also argued that the meaning of g'di is still narrow enough to exclude birds, all the undomesticated kosher animals (for example, chevrotains and antelope), and all of the non-kosher animals . The Talmudic writers had a similar analysis, but believed that since domesticated kosher animals (sheep, goats, and cattle) have similar meat to birds and to the non-domestic kosher land - animals, they should prohibit these latter meats too, creating a general prohibition against mixing milk and meat from any kosher animal, excepting fish . </P> <P> The term non-kosher means something is not allowed as food--non-kosher animals (e.g., pigs, camels, and turtles) were already generally prohibited, and questions about the status of mixtures involving their meat and milk would be somewhat academic . Nevertheless, the lack of a classical decision about milk and meat of non-kosher animals gave rise to argument in the late Middle Ages . Some, such as Yoel Sirkis and Joshua Falk, argued that mixing milk and meat from non-kosher animals should be prohibited, but others, like Shabbatai ben Meir and David HaLevi Segal, argued that, excluding the general ban on non-kosher animals, such mixtures should not be prohibited . </P> <P> Rashi expressed the opinion that the reference to mother's milk must exclude fowl from the regulation, since only mammals produce milk . According to Shabbethai Bass, Rashi was expressing the opinion that the reference to a mother was only present to ensure that birds were clearly excluded from the prohibition; Bass argued that Rashi regarded the ban on boiling meat in its mother's milk to really be a more general ban on boiling meat in milk, regardless of the relationship between the source of the meat and that of the milk . </P> <P> Substances derived from milk, such as cheese and whey, have traditionally been considered to fall under the prohibition, but milk substitutes, created from non-dairy sources, do not . However, the classical rabbis were worried that Jews using artificial milk might be misinterpreted, so they insisted that the milk be clearly marked to indicate its source . In the classical era, the main form of artificial milk was almond milk, so the classical rabbis imposed the rule that almonds must be placed around such milk; in the Middle Ages, there was some debate about whether this had to be done during cooking as well as eating, or whether it was sufficient to merely do this during the meal . </P>

Not boil a kid in its mother's milk