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Kant begins by specifying what it is to have a duty to a subject: a "duty to any subject is moral constraint by that subject's will." An obligator (a being to whom one can have a duty, a being capable of "active obligation") must have a will that can impose a moral constraint upon the obligated, and the obligated (one capable of "passive obligation") has a will that can be constrained by the obligator. This analysis leads Kant to articulate two conditions for genuine moral status: we can be obligated only to a being that is both (i) a "person," a being with a (certain kind of) will, and (ii) is "given as an object of experience." Kant claims that the former condition excludes objects "other than persons," namely "(non-human) objects" such as "mere inorganic matter [der bloße Naturstoff] (minerals), or matter organized for reproduction though still without sensation (plants), or the part of nature endowed with sensation and choice (animals)." While these beings are given as objects of experience, Kant thinks they lack a will that can impose moral constraint upon us. Kant's latter condition excludes "superhuman," "absolutely imperceptible" spiritual persons (such as God, angels, and demons) "who cannot be presented to the outer senses" (MdS 6:442). Insofar as these beings cannot be given in experience, Kant argues, we are unable to cognize them or their needs, and we are unable to intentionally affect their condition through our