In the philosophy of Leibniz, the ultimate logical decision was God’s choosing of the finest of all worlds. God is both a necessary entity and author of the universe in that he creates the world that he considers the finest of all worlds. (Possible Worlds in the Tahâfut al-Falâsifa: Al- Ghazâlî on Creation and Contingency and Knuuttila, Duns Scotus and the Foundations of Logical Modalities. On the concept of “possible world” before Leibniz, see Knebel, Leibniz, Middle Knowledge, and the Intricacies of World Design.) He makes and ends the universe in principle — the world cannot exist and ceases to exist in any other manner. In creation, God realizes an unlimited number of compatible substances which are ready to exist. All elements reside before creation merely as concepts in God’s comprehension. All possibilities (truths of fact) in certainly conceivable worlds are true, but in every world, there are necessary truths or truths of reason. Each substance follows its unique scheme of evolution (the individual concept), which only God can foresee. Leibniz’s objection to the freedom of indifference is the foundation for the notion that only one best world exists. Choice in a condition of balance (two or more items of equal importance) involves the freedom of indifference and cannot be permitted, as there must be some difference or benefit that the best world has, and other people have not. God discovers in his knowledge this most acceptable alternative, which provides him enough cause for his choice. Freedom of indifference involves behaving without reason because there is no reason to prefer one to another. He wrote to Clarke Leibniz in his third letter:
“…this is plainly maintaining that God wills something without any sufficient reason for His will, against the axiom or the general rule of whatever happens. This is falling back into the loose indifference I have confuted at large and showed to be absolutely chimerical even in creatures and contrary to the wisdom of God as if He could operate without acting by reason.” (G VII, p. 365; L,p. 683. See also G VII, p. 301 and the 2nd letter to Clarke, G VII, p. 356.)
In his work, Versuch einiger Betrachtungen über den Optimismus (1759). Immanuel Kant explored some reasons against this theory in an attempt to reflect on optimism. According to him, a conceivable world needs to exist beyond which there is no greater thing. It does not follow from this that there must eventually be a single perfect world as if two or more potential worlds were just as flawless, neither would be ideal since both of them would have the same degree of goodness.
Kant tried to defend the concept of Leibniz by supposing that the ultimate perfection of a subject must be matched to its degree of actuality. Two realities cannot, according to him, be differentiated from each other as such – one might argue simply that one thing is there and not the other. Thus realities differ only in magnitude and not in quality from one other. He reasoned from this that two distinct universes could never have the same degree of reality, and hence two worlds could not be equally wonderful and flawless. There is only one ideal universe, therefore. Kant later suggested an alternate option to see this world as the finest since God thus assessed it. Because God’s judgment never goes wrong, this world is indeed the finest. It follows. Since God is wholly excellent and all-knowing, it seems evident that He decided to create the finest worlds imaginably. There are other difficulties that
Leibniz has more or less disregarded or that in his works remain unclear. One is: why did God choose to create a world? Naturally, God is an independent being without any external tasks. (Kant, Theoretical Philosophy, 1755-70, p. 72.)
He did not have to create the world more flawless, as he was already the most perfect. He also had no duty to build a universe for anyone. However, one assumes that if he built any universe, he would be more flawless because historically, he is a wonderful person. (Blumenfeld, Is the Best Possible World Possible? p. 170.)
The creation was made by the will of God (In the Essais de Theodicée (1710),) Leibniz claimed that God determined to create the universe by the free movement of His goodness. The good in the finest conceivable world prompted him to build it in his consideration between all potential worlds. His desire was directed to the world’s virtue, and he was inclined to pick it from among an endless number of potential worlds, but his decision did not compel.
However, if the objective good dictates God’s decisions, how can He choose otherwise? If He cannot, His will is not free. Therefore, this, again, would mean that there was no absolute contingency in the actual world. There is no doubt that Leibniz wished to avoid this kind of necessitarianism concerning God’s choice since he stated this on numerous connections, usually in the context of his criticism of Spinoza. For example, in Essais de Theodicée, §173, he wrote:
“Spinoza went further: he appears to have explicitly taught a blind necessity, having denied to the Author of Things understanding and will, and assuming that good and perfection relate to us only, and not to Him…he teaches that all things exist through
the necessity of the Divine nature, without any act of choice by God. We will not waste time here in refuting an opinion so bad and indeed so inexplicable.” (G VI, p. 217; H, p. 234. . )
There is another question of Leibniz, having been able to sidestep the difficulty. Therefore, this has led to a lengthy debate on his position on contingency and necessity, which we shall only make a short reference to Robert M. Adams’s most famous view of God’s freedom in his paper “Leibniz’s contingency theories.
“ Adams believes that Leibniz was both a compatibilist (subscribing to the idea that despite determinism, one may choose freely) and a determinist, but he sought to express his beliefs in a non-offensive way to escape the harsh criticism that Spinoza got. (Adams, Leibniz: Determinist, Theist, Idealist)
In his early views, Adams quotes the following line from Leibniz’s 1671 letter to Wedderkopf:
Since God is the most perfect mind, however, it is impossible for Him not to be affected by the most perfect harmony, and thus to be necessitated to the best [optimum] by the very ideality of things…Hence it follows that whatever has happened, is happening, or will happen is best and therefore necessary, but…with a necessity that takes nothing away from freedom because it takes nothing from the will and the use of reason.”(A II, 1, p. 117; Adams, Leibniz: Determinist, Theist, Idealist, pp. 10-11.)
Adams contends that Leibniz took an essential viewpoint, holding that God was required to create the finest due to his nature. He reportedly afterward changed his stance and stated the universe itself and its objects were not necessary but contingent since alternative realms in which such things did not exist were feasible. Since there were other conceivable universes before the decision of God, the current world was dependent. (Adams, Leibniz: Determinist, Theist, Idealist, pp. 12-13.) In other words, God had to pick among numerous alternative universes. De libertate et necessity (1680-84(?))(A VI, 4, pp. 1444-49) and Essais de Theodicée, § 235 are presented in this argument in a memoir:
“God chooses among the possibles, and for that very reason, He chooses freely and is not compelled; there would be neither choice nor freedom if there were but one course possible.” (G VI, pp. 258; H, pp. 272-73.)
Adams sees this argument as the most successful defense of contingency in the present world for Leibniz. It is connected with the dichotomy between hypothesis and metaphysical necessity. The first is the need for preconception (feasible but not as desirable), while the latter is the actual antithesis of contingency (the opposite of which is inconceivable). (The Philosophy of Leibniz, p. 121; On the concept moral necessity, see Knebel, Wille, Würfel und Wahrscheinlichkeit, p. 127f.) When God has numerous alternatives, he is not necessary metaphysically to pick this world, as he may always choose another world that is conceivable but less desirable than the current one.
So Leibniz did not allow God to act utilizing metaphysical (blind) necessity, negating His understanding and decision, but claimed that His hypothetical or moral obligation was linked to His knowledge to select the greatest of all conceivable worlds. If God acts according to moral necessity, He is driven by good reasons. In other words, without tying him, these causes lean to Him.
“…even though it is certain that God would always choose the best, this does not prevent something less perfect from being and remaining possible in itself, even though it will not happen, since it is not impossibility but imperfection that causes it to be rejected.” (Discours de metaphysique, §13). A VI, 4, p. 1548; AG, p. 46.)
Adams contends that Leibniz could not escape the conclusion that God, as an absolutely perfect being, acts what is best, which was shown and hypothetically essential. (Adams, Leibniz: Determinist, Theist, Idealist, pp. 39-40. Thomas Aquinas also discusses this question in Summa Contra Gentiles. See Kretzmann, The Metaphysics of Creation, pp. 131-36.)
Leibniz recognized the hypothesis that freedom is something. Three requirements were laid forth in §288 Essais de Theodicée: intelligence (a clear understanding of the purpose of deliberation), spontaneity (the agent is the source of the action)(Rutherford, Leibniz on Spontaneity, p. 161f; see also Murray, Spontaneity, and Freedom in Leibniz and Greenberg, Leibniz Against Molinism.) and urgency (the exclusion of logical and metaphysical necessity). (See G VI, p. 288.) In the context of the framework mentioned above, it may be argued that God freely selects the universe which He creates through His attributes (foresight, omnipotence, and contingent choice). However, this position might be questioned; if God determines that a specific world is the greatest, it seems that He cannot pick another world since the decision would go against His nature, in other words, His knowledge and kindness. So it would appear that he was not free after all in his choices.
Adams’s answer gives another Leibnizian defense of the current world’s contingency, namely that the argument that this world is best depends. (Leibniz Society Review 6, pp. 61-126.) Thus, while it may be hypothesized that God picked the finest, this world does not have to be the greatest. Whereas the former is the result of the essence of God, the latter cannot be shown by limited analysis and is thus contingent. (Adams, Leibniz: Determinist, Theist, Idealist, pp. 24-27) To adopt a wording suggested by John Carriero, even though God outwardly necessitates the life of this world (God is ethically required to pick the best world), it is contingent as the world is not internally needed (it is not necessarily the best of all possible worlds). (Carriero, Review, p. 63. On Carriero’s criticism of Adam’s views, see p. 66f.) These two defenses (as provided by Adams) are enough to show that the Leibnizian system avoids blind, metaphysical necessity, although certain subtleties, such as the exact nature of infinite analytics, are not entirely apparent. (See Sleigh, Leibniz and Arnauld, pp. 83-89.) Adams contends that moral necessity in his most recent essay on Leibniz’s metaphysics is fundamentally related to final causes instead of effective causes because ultimate causes lead to good. Hypothetical necessity applies to God and the spirits, whose appetites are connected with the ultimate causes. Although God cannot be wrong in his judgment, humanity’s good thinking is misleading, as is proven in Parts II and III by their limited cognitive capacity. According to Adams, the choice of God for the best of all worlds was the most significant and fundamental instance in the Leibniz system of things for the last cause. Leibniz, therefore, distinguished himself from Spinoza, who thought that only effective causes existed in nature. (Robert Merrihew Adams, Moral Necessity, p. 187. See also Spinoza, Ethics I, prop. XVI.)
Adam’s interpretation of the beliefs of Leibniz on the liberty of will in the choice of God appears to be plausible. Concerning the question of human freedom, I tend to support Robert Sleigh, who argues that in principle, human choices are unpredictable by other created beings (although predicted by God); that is, they do not always follow the greatest apparent good although in judgment about the good they do not err. (Sleigh, Leibniz on Freedom and Necessity, pp. 249-54.) Men might act erratically, in other words, select incorrectly, even though they recognize the ideal deed done in a given scenario. Naturally, this is impossible for the excellent divine decision-maker, whose thoughts are not subject to such difficulty.