Here are some considerations pertinent to this topic, from my essay “Volitional Synapses” in Objectivity V2N2 (1995).
“Leibniz was right, I think, to emphasize hypothetical necessity in human freedom. The hypothetical in the phrase is what we need to focus on more than did Leibniz. ‘It is there that free will plays its game’ (T §147, emphasis added).
“When one rolls a die, it is true that the outcome is completely determined by the die’s initial conditions (its conditions upon leaving the hand) and the conditions it encounters along the way before coming to rest. Its motion between toss and coming to rest is lawful all along the way. Suppose the die collides with a busy housefly on the way down. The effects of that collision are lawful too. Given that die and fly are on a collision course, certain lawful results follow. But where is the lawful connection between this die and this fly being on such courses that will bring them to the same region at the same time? Nowhere. There is no such lawlike connection. We know that, and we know we should not invest in trying to find such a law. Existence is thicker in facts than laws.
“Similarly, when the die lands on the table, there will be lawful interaction. It will not be practical to predict the outcome (as opposed to guessing the outcome) because we shall not normally be able to know the die’s initial conditions with enough precision and because on impact the die’s edges and corners will act as pivots of unstable equilibria. Nevertheless, we have the usual mechanical laws governing the interaction. But where, oh where, is the lawful connection between this die and this table being on such courses that will bring them into contact? Nowhere. We control things by adjusting constraints. We cannot adjust the laws themselves.
“[Leibniz replies:] ‘But such a chance, such an absolute and actual fortuity, is a chimera which never occurs in nature. All wise men are agreed that chance is only an apparent thing, like fortune: only ignorance of causes gives rise to it’ (T §303; cf. Rand 1973, 28–29). We are, he says, admitting ‘something which happens without the existence of any cause or reason for it’ (T §362).
“No. Far be it from me to deny the principle of substantive propagation. That is the principle that says the way things are grew out of the ways things have been (Boydstun 1991b, 35–36). The die has its causal history and so does the fly, but the trajectory of die was independent of the flight path of fly. Causality and other nomic connection and real chance all coexist in perfect harmony.
“When we throw a die and call it, the lack of correlation, the chance, is as Leibniz says: a matter of ignorance. We do not know the initial and subsequent conditions finely enough to do anything but guess. When we throw two dice repeatedly and simply record their outcomes, we find there is no correlation between the two sequences. That is real chance, having nothing to do with our ignorance. . . .
“Leibniz took issue with Aristotle over real chance, and naturally enough, he also took issue over truth in future contingents. For now I shall leave open a miniscule possibility that Leibniz could be right concerning truth in future contingents for a case of two flies having a mid-air collision. To know for sure, we should have to examine how the concepts intention and accident, as well as representation and error, might apply to flies. And we should have to have a comparative look at their control circuitry. . . . Be the flies as they may, in our case of the collision of die with fly, which depends on a human free decision, I am even more confident that Leibniz was wrong and Aristotle right about truth in future contingents (cf. Rand 1973 25–29).
“Aristotle concluded: Yes, it is now true that tomorrow there will either be a sea battle or not be a sea battle, not both. It is not now true that the one that will be tomorrow is. That there will be a sea battle tomorrow is not now true nor false, because that reality is for now indeterminate (de Int. 9).”