“Another area of corruption lies in the ideal of achieving pure unity without diversity in the categories that we use in logic. We should return for a moment to the point made earlier about the relation between one and many. Consider a particular case, namely, the relation between the generality of being “human” and the particular cases of particular human beings. The one is “humanness.” The many are particular humans, Socrates and Plato and Aristotle—as well as you and me. In practice, our knowledge of the one, of what it means to be human, is bound up with the knowledge of par- ticular human beings, including self-knowledge. And all this knowledge is also bound up with knowledge of God, in whose image we are made.
We have said, “in practice.” Within finite human experience, and within human use of ordinary language, the one and the many belong together. But if Christian theology is right about the Trinitarian character of God, and the dependence of human thought on divine thought, the expression “in practice” can be extended to “in theory” as well. God’s knowledge is also “contextualized” knowledge, that is, his knowledge exists in the context of the interaction and mutual indwelling of the persons of the Trinity.
In natural language, then, the descriptive term human has meaning in interaction with particular human beings like Socrates and ourselves. We may say, “Socrates is human” and “Plato is human.” And in each sentence, the word human is subtly colored by its association with a particular example or instantiation of the classification human. When we consider the assertion “Socrates is human,” Socrates is our prime example of humanity. We are invited to think of what it means to be human with Socrates as our prime example. What might come to mind? To be human means to think, to exercise reason. To be human means entering into dialogs and discussions. To be human includes not knowing everything, and includes the opportu- nity, if one is inclined as Socrates was inclined, to admit one’s ignorance on certain subjects.
Instantiation and classification interpenetrate, rather than being purely isolated. The ultimate basis for this interpretation lies in the plan of God to create human persons in analogy with divine persons. So we also take into account the persons of the Trinity—the Father, the Son, and the Holy Spirit—who exist not only as distinct persons but as persons in relationship. Likewise, the word “human” has contrast, variation, and distribution.
In contrast to this complexity, logical analysis often wants to have an ideal, context-free symbol, the word human, which is often regarded as having purely identical meaning no matter to which item it applies. This ideal wants unity without any diversity in the label human. If we relate this ideal to the question of God, an ideal of unity without diversity is unitarian. Unitarianism is the belief that there is one God (unity), but not a Trinitarian God. God is one, but not three persons. This ideal is innately untrue to real- ity, but true to the desires for human autonomy. In other words, there is an underlying religious motivation.”
(Poythress, Logic, 173-74)