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Dynamical Similarity and the Problem of Evil
God, Grace, and Creation: The Annual Publication of the College Theology Society
  • Brad Kallenberg, University of Dayton
Document Type
Book Chapter
Publication Date
Discussions of evil commonly fault God for not “doing something.” Defenders of God respond that God had good reasons for not “doing something.” Detractors observe that if a human being can snatch the toddler from the path of the oncoming bus, why does not God snatch the bus from the path of the oncoming toddler? The underlying assumption in such discussions is that God’s “doing something” is similar to humans’ “doing something.” If human beings bear the image of their Creator as the Abrahamic faiths maintain, it is natural to suppose that divine action is similar to human action. But what sort of similarity is in play? That more than one kind of similarity can be brought to bear is often overlooked. The everyday garden variety of similarity may be illustrated by imagining two congruent triangles: A glance will show that that the triangles are similar because their corresponding angles are the same. And though the sides are of different lengths, they are correspondingly proportional: if the bottom side of the smaller triangle is half that of the larger, then its other two sides will also be half the length of their counterparts. Here the simple scale is 1:2. The units of measurement are unimportant. Whether one measures in inches or centimeters, the same ratio always holds. In other words, “4 in. to 8 in.” constitutes a ratio of 1:2 as does “10.1 cm. to 20.2 cm.” Because the units of dimension drop out when the scale is calculated, this kind of similarity has been called “dimensionless similarity.” When atheistic philosophers of religion complain that God failed to “do something” about instances of gratuitous evil, they imagine the kind of divine agency being debated is a scaled-up version of human action: God’s action (should God exist) is similar to human action only bigger, stronger, faster. The employment of dimensionless similarity is a bewitching conceptual mismove that perpetuates both theological and philosophical confusion. At least as early as Augustine, Christians noted that there can be no proportion between God and creatures.3 Of course, atheist philosophers of religion cannot be held to Christian dogmas. But the underlying confusion is also philosophical. The Christian notion of God cannot be arrived at by a strategy that presumes dimensionless similarity (i.e., numerical proportion) and then adjusts the scale to account for an “infinite” term. Fortunately, the kind of modeling that relies upon dimensionless similarity is not the only kind of modeling human beings can employ. Unfortunately, however, the notion that may assist in the problem of evil is .not one that can simply be snipped out of one context and pasted into theodical discussion. It is a technical term, one on the same level of complexity as “partial differential equation” or “myocardial infarction.” As such it must be seen against the backdrop of its use-in-practice to get the point.
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Orbis Books
Place of Publication
Maryknoll, NY
Peer Reviewed
Citation Information
Brad Kallenberg. "Dynamical Similarity and the Problem of Evil" God, Grace, and Creation: The Annual Publication of the College Theology Society Vol. 55 (2010)
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