"You are free to examine the Magi's data recorders. There is no record of any such incident."
Human (人: hito, 人間: ningen, 人類: jinrui), as used in the Evangelion universe, most often refers to Lilin (Mankind). However, the many "nontraditional" uses of "human", "person", etc., indicate that a more expansive concept of humanity exists, although it is never precisely defined.
Over the course of the show:
- Adam is referred to as the "first human".
- Lilith is said to be a "person" and "human". (Though note that this is after it has fused with both Adam and Rei 3.)
- The Evas are called "artificial humans". Ritsuko later simply refers to them as "human" (affirming Shinji's inquiry regarding their status as "people").
- Adam's children are described as "humans who cast aside human form".
- Rei says that Kaworu is as human as she is -- hence they both are human.
- And, of course, the Lilin are humans.
This effectively means that everything designated an "Angel" within the show, along with some "off the list" Angelic entities (the Evas and Rei), are "human" as well, raising the question of what the exact distinction between "Angel" and "human" is, if any exists at all. Since Humans have also been referred to as the 18th angel, the distinction could be even harder to spot.
The answer may lie in the common origin of all these entities: that is, the First Ancestral Race. They were a humanoid species, and it would probably not be a stretch to consider them the original form of humanity. Nothing conclusive is known about the FAR's motivations, although it is possible that the Seeds of Life were created as human gods made in the FAR's image for the purpose of preserving humankind. This would be on both a physical and metaphysical level, with humanity embodied by each individual Seed in body and soul, and, additionally, each Seed would be intended to propagate a different variation of humankind.
With Adam, that variation was to be a race of gods who could take on any form imaginable, but still be intrinsically human. (Sandalphon shows that Adam's Children begin life as humanoids, and even once they "cast aside" this form they retain their original genetic information, evidenced by the analysis done on Shamshel's corpse.) With Lilith, a human species would arise through (possibly "guided") evolution from microscopic beginnings, acquiring a remarkable resemblance to the "original model" of humanity despite taking a completely different developmental path. The ultimate purpose of these and the other descendant versions of humanity is to enable the souls of the First Ancestral Race -- which were collected and distributed between the Seeds' Chambers of Guf -- to life on in some form beyond their species' physical extinction.
Ultimately, "human" may simply refer to the First Ancestral Race and all members of their spiritual (and, to a lesser extent, physical) legacy.
- These three Japanese terms vary in nuance, although they can all be translated to the English word "human" (depending on context). They are also the three words used to refer to "human", "person", "humanity", "mankind", etc., in Evangelion. For example, "artificial human [ningen]" (the Evas) and "humans [jinrui] that cast aside human [hito] form" (Adam's children).