מִכְּלָל שֶׁנֶּאֱמַר (דברים יד ו) "וְכָל בְּהֵמָה מַפְרֶסֶת פַּרְסָה וְשֹׁסַעַת שֶׁסַע שְׁתֵּי פְרָסוֹת מַעֲלַת גֵּרָה" שׁוֹמֵעַ אֲנִי שֶׁכָּל שֶׁאֵינָהּ מַעֲלַת גֵּרָה וּמַפְרֶסֶת פַּרְסָה אֲסוּרָה. וְלָאו הַבָּא מִכְּלַל עֲשֵׂה עֲשֵׂה הוּא. וּבְגָמָל וּבַחֲזִיר וּבְאַרְנֶבֶת וּבְשָׁפָן נֶאֱמַר (ויקרא יא ד) (דברים יד ז) "אֶת זֶה לֹא תֹאכְלוּ מִמַּעֲלֵי הַגֵּרָה וּמִמַּפְרִיסֵי הַפַּרְסָה" וְגוֹ' הֲרֵי לָמַדְתָּ שֶׁהֵן בְּלֹא תַּעֲשֶׂה וְאַף עַל פִּי שֶׁיֵּשׁ בָּהֶן סִימָן אֶחָד. וְכָל שֶׁכֵּן שְׁאָר בְּהֵמָה טְמֵאָה וְחַיָּה טְמֵאָה שֶׁאֵין בָּהּ סִימָן כְּלָל שֶׁאִסּוּר אֲכִילָתָם בְּלֹא תַּעֲשֶׂה יֶתֶר עַל עֲשֵׂה הַבָּא מִכְּלַל אוֹתָהּ תֹּאכְלוּ:
Since it is written [Deuteronomy 14:6]: "Any animal that has split hooves, [whose foot] is divided into two hoofs and chews the cud, [this may you eat]," one may derive that any animal that does not chew its cud and have split hoofs is forbidden. A negative commandment that comes as a result of a positive commandment is considered as a positive commandment. With regard to the camel, the pig, the rabbit, and the hare, [Leviticus 11:4] states: "These you may not eat from those which chew the cud and have split hoofs." From this, you see that they are forbidden by a negative commandment, even though they possess one sign of kashrut. Certainly, this applies to other non-kosher domesticated animals and wild beasts that do not have any signs of kashrut. The prohibition against eating them involves a negative commandment in addition to the positive commandment that is derived from "This may you eat."
