Middle Knowledge, Truth-Makers, and the Grounding Objection

1. Middle Knowledge, Truth-Makers, and the Grounding Objection

2. Reconciling God’s Omniscience with Human Freedom • Classical Christian theism holds: • God has exhaustive knowledge of the future. • Human beings are free creatures such that they determine their free actions (including their sins), not God. • But, if God knows what we will freely choose to do, how can it still be said that we freely choose our actions? Don’t our actions have to happen by necessity if God knows they will happen?

3. One Solution • Argue that it does not follow from the fact that God knows what we will freely do, that we do not freely do it. • Of the different sorts of knowledge God possesses, God knows what any free creature (possible or actual) would do in any circumstance that creature would be placed in. • This knowledge is referred to as God’s middle knowledge.

4. Middle Knowledge • God’s middle knowledge is “between” (hence “middle”) His natural knowledge and His free knowledge. • Natural: God’s knowledge of necessary truths like All squares have four equal sides or 2 + 2 = 4. • Free: God’s knowledge of contingent truths, like Grass is green, which are known because of the world God chooses to create. • In the actual world, grass happens to be green, but it could have been yellow if God would have made the world differently.

5. Middle Knowledge • If God has middle knowledge, then He can create a world based on what he knows the free creatures in that world would freely choose to do. • God knows what these creatures would do before they exist and independently of His decision to create the world.

6. Counterfactuals • A counterfactual is any proposition (statement, sentence, thought) that is about the way the world will be, could be, or could have been but isn’t. • For example: • “Were Professor Roberts to have attended Wheaton he would not have married Jessica” is a counterfactual statement. • Counterfactuals of creaturely freedom are counterfactuals about the free decisions of creatures.

7. The Correspondence Theory of Truth • For any true proposition (like The sky is blue) there is something about reality that corresponds to the truth of this proposition. • In this case, the fact (or state of affairs) of the sky’s being blue corresponds with the proposition that the sky is blue. • This is the traditional and commonsense view of truth.

8. Truth-Makers • There are various versions of the correspondence theory of truth. • One is truth-maker theory. • Truth-maker theory holds that for any true proposition, there exists some concrete (physical) object(s) that makes it true. • In other words, for every truth, there must exist a ground for that truth, a truth-maker. • This “making” is not causal; it is a logical “making.” • The existence of the ground entails the truth of the corresponding proposition.

9. The Grounding Objection • If truth-maker theory is right, then it seems that there is no ground, no existing concrete object, that can make counterfactuals of creaturely freedom (about non-existent creatures) true. • Since the counterfactuals of creaturely freedom are about creatures that God has yet to (and may not) create, there is no ground for their truth, and therefore God could not know them as true propositions.

10. Answering the Grounding Objection • The grounding objection assumes a truth-maker theory of truth. • But there are many reasons to think that the truth-maker theory is a flawed theory.

11. Are There Truth-Makers for All Propositions? • If truth-makers are concrete (physical) objects, then many propositions, though true, or possibly true, seem to lack a truth-maker.

12. Examples • Propositions that could be true, but are false (No physical objects exist) • Propositions about all of some object (All ravens are black) • Propositions about non-existent or past-existent objects (like Dinosaurs are extinct or Santa is jolly or Smurfs don’t exist) • Moral propositions (Torturing babies is wrong). • Propositions about the past and the future (Napoleon lost the Battle of Waterloo and The U.S. President in 2070 will be a woman). • Propositions about abstract objects (7 is a prime number)

13. Preserving the Correspondence Theory of Truth without Truth-Makers • If we want to preserve the intuition that any true proposition is true because it corresponds with reality, how can we do so without truth-makers?

14. Suggestion #1 • Construe facts as having tensed properties and as including counterfacts. • Tensed properties: • The proposition Dinosaurs are extinct is true in virtue of the fact that the world (or some relevant part of it) is such that it has the property of being such that dinosaurs lived but no longer live (a past-tense property). • Counterfacts: • The proposition that Professor Roberts wouldn’t be married to Jessica had he attended Wheaton is made true by the counterfact of Professor Roberts being such that had he attended Wheaton he wouldn’t have married Jessica. • This solution may actually preserve truth-maker theory depending on the acceptability of tensed properties and counterfacts. • But how can it deal with counterfactuals of creaturely freedom about yet-to-exist persons?

15. Suggestion #2 • Redefine truth-makers to include abstract as well as concrete objects. • Since propositions are abstract (non-physical) objects, we can now include propositions as truth-makers, not just truth-bearers. • For example, the proposition that the U.S. president in 2070 will be a woman is made true by the proposition that a woman is president having the property of being true in 2070. • Similarly, the proposition that Professor Roberts wouldn’t be married to Jessica had he attended Wheaton is made true by the proposition that Professor Roberts isn’t married to Jessica having the property of being true had he attended Wheaton or being true in a world where he attends Wheaton. • This solution looks like it requires the existence of possible worlds, though.

16. Suggestion #3 • Construe states of affairs as abstract objects that do not include concrete objects. • States of affairs are like propositions, only they don’t bear truth values (e.g., snow’s being white) • Let a world be a maximal state of affairs that includes every state of affairs S and precludes every state of affairs S*, where S* is the contrary of S. • If S is snow’s being white, S* is snow’s not being white. • All tensed (past and future) propositions about objects in the actual world are made true by the sequenced states of affairs that make up the actual world. • Logically prior to God’s creative decree, counterfactuals of creaturely freedom are made true by the states of affairs included in any world that God might create.

17. Summary • God’s middle knowledge of counterfactuals of creaturely freedom is designed to reconcile divine foreknowledge and human freedom. • Truth-maker theory seems to count against the truth of counterfactuals of creaturely freedom, the subject of God’s foreknowledge. • A correspondence theory of truth can still be preserved by redefining or eschewing truth-makers and thereby saving the doctrine of middle knowledge.