Investigating the "Primary Principle" in purity and prohibition of eating animals meat

Religious instructions contain some orders in the field of nutrition, including the permission or prohibition of food consumption. It is certainly permitted to eat the meat of some animals such as sheep and prohibited to use the meat of some other animals such as pigs, but it is not clear the permission or prohibition of some other animals, such as giraffe, kangaroo, deer or animals which are the result of sheep and pigfertilization. In such cases that there is no specific authentic tradition, some have permitted eating them by using the Rule of Permission (Helleiiat) and others have forbidden them by using the Principle of Impurity (Tazkiah). This article seeks to study the fundamentals of the scholars’ ideas in relation to the mentioned rules and principles. In this paper, the author defends the theory of those who use "The Principle of Permission (Helleiiat)".