“Exemplar Causality” can be found in Bonaventure and Aquinas. The idea is old and its mention in conversation just the other day has sent me off like a rocket.
The ancient question of transformation, reform, development, progress is always due attention. It is in the most significant sense the question of change, with the edition of a scale of values, and direction toward the good.
For Aristotle the causes of change are four in number: material (stuff that the change takes place in), efficient (agency, source of motion), formal (essential kind) and final (goal). So, the painting has its material cause in paint and canvas, it efficient cause in the painter, its formal cause in the essence of what makes a painting a painting, and its final cause in the goal of the painter worked out from idea to image on canvas.
But imagine the painter is a realist and painting reality. He will then model his image on something external, a standard by which he measures his own production. That reality becomes the physical instantiation, an exemplar by which his act and copy is measured. Consider the human who seeks self-development. What he needs is an image of the perfected human. That which provides the reality (more than just idea, more than just a recipe or plan) is the exemplar which causes the development by the essential stimulus provided the the agent who acts toward the exemplar. The exemplar puts meat and bone on the formal idea.
Without answering whether there is only one exemplar cause, or answering questions about what features make it an exemplar, we are faced with a kind of causality that is essential to change as development, but does not result in the effect without further additional causal elements.
The modern, who post scientific revolution and the modern philosophical rejection of final causes (and exemplar causes), preserves at best the efficient causality that is present when one billiard ball (or atom) encounters another. But the second ball (or atom) is redirected in some sense passively by the transfer of impetus from the first cause to the second effect. The story is simplistic, but all that the modern need do in his salvation story is conceive of Christ as a billiard ball who crashes into and alters his course. His (effect) position is passive.
Bu this is both deeply minimalist and reductive in its notion of causality, sparingly rejecting all the other insights that might provide for the understanding of change as development. And it seems to do something else. It ignores all the real work that necessary and ineliminable from the project of development and change-in-a-direction.
I can already hear claims (screams) of heresy regarding “works”. The modern is ready to say it is EITHER all the savior OR not all the savior, and I must choose. But this simply restricts the notions of causality available for explanation and ignores any hierarchy that may be present among them. If Christ is the essential exemplar cause, by providing that which otherwise I could not aim at, then he is, in a meaningful sense, everything, without which not.
Why do I strive to complicate the story? My experience with “salvation” is that it is AT BEST a process. That process is AT BEST difficult. Anyone preaching otherwise is selling something, a snake-oil salesman who offers passive directional change in a reality where it ONLY occurs in the midst of focused aim, disciplined organization of life, courageous overcoming of temtation, and temperately balanced use of earthly goods.
None of it would be possible without the exemplar. And so the exemplar is the cause of salvation, and transformation, and onward.