Spinoza, Leibniz, and the Power of Necessity

When we reflect on past events, it is quite common that we fall into the habit of saying things like, "If only had I not gotten hurt" or " If only had I went to a different school" or " If only had I married a different person". These are certainly entertaining thought experiments. Our intuitions tell us that it is quite possible that things could have happened in a different way than they did-- indeed, some events come so close to happening that it is easy to assume things could have readily gone the other way. One contemporary example is the proposition " George Bush could have lost the 2004 election." Can we say that this proposition is true? If we truly ask ourselves, " Could the world have happened any other way than which it did?", can we justifiably say that these other, non-actualized possibilities existed? Dutch philosopher Baruch Spinoza, carefully painting a philosophical system based on necessity, seems to argue that we can't justify these non-actualized possibilities. On the other hand, the German Gottfried Leibniz seems to argue that, in other possible worlds, we can justify these possibilities. On closer inspection of each of these philosophers systems, however, it becomes clear that Leibniz faces a difficult time in answering Spinozian objections and thus may fall victim to Spinoza's system. In fact, if we consider that Leibniz is arguing against Spinoza, we could justifiably say that Leibniz' arguments cannot explain away Spinoza's necessitarian picture.

Spinoza's necessitarianism is a direct derivation from the premises and conclusions established from his argument for "substance monism"-- that is, the idea that there exists but one possible substance (God) and that this substance necessarily exists. In his argument, Spinoza invokes the principle of distinction--- that is, the principle that things are distinguished by virtue of differences in modes or attributes (Ethics, Ip4). Since we cannot distinguish two substances by appealing to their modes, then two substances cannot share attributes (Ip5). Furthermore, Spinoza argues, one substance cannot be produced by another substance, for that would require at least one shared attribute between the substances (Ip6) However, since he already established that two substances cannot share attributes, there can be no causal relation between the two. Therefore, Spinoza concludes, there are no merely possible, but non-existent substances.

To complete the argument, Spinoza then seeks to prove that at least one substance exists. He begins with the a posteriori claim that something exists (Ip11d) and must exist in itself, or through another thing (I Axiom 1). This existing "thing" cannot be a mode or an attribute, since modes and attributes clearly cannot exist without substance (Id5) Therefore, at least one substance exists. For Spinoza, it would be absurd to argue that God (so defined as infinite substance) did not exist while a finite substance existed (Ip11d). Therefore, since nothing is absurd (everything needs a sufficient reason for its existence), then God necessarily exists. Since God's existence and the existence of other substances are mutually exclusive (since one substance cannot cause another substance and an infinite substance, by definition, cannot be "caused"), God is the only possible substance (Id6, Ip5)

Spinoza has now established that God necessarily exists, and that God is the only possible substance. The question now becomes, "By virtue of what are things said to be caused by God?" Because of our finite minds, Spinoza says, we tend to think of God's "will" and "intellect" causes things, analogous to the way we perceive our "will" and "intellect" cause things. However, Spinoza argues, "infinitely many things in infinitely many ways" follow necessarily from God's necessary existence (Ip16); God does not act from freedom of will, and furthermore, neither do we (Ip17). Thus, Spinoza argues (and, as we will see, Leibniz argues differently) that this world is the only possible world. There is no place for contingency in Spinoza's necessitarian system, because everything caused by God follows necessarily from his nature (Ip29). In other words, things could have been brought about no other way than the way they have already occurred. (Ip33)

So, as we consider the statement, "George Bush could have lost the 2004 election" Spinoza's necessitarian system requires this statement's falsity. To falsify the statement, let us assume its place it in the Spinozian system, and prove its invalidity through a reductio ad absurdum. So, in a different world, we shall assume, George Bush lost the 2004 election. A different world would require different characteristics from the world we know. For this world to have different characteristics, "God" would require different characteristics, for since all events follow necessarily from God, any alternative events in a different world clearly must be caused by a different necessity. By virtue of our assumption, we now have Actual God A, which caused George Bush to win the 2004 election, and Possible God B, which caused George Bush to lose the 2004 election. But Spinoza has already established that there are no merely possible, but non-existent substances. So, by virtue of our assumption,, God B, by merely being possible, must exist. Actual God A, having already been actualized, must exist. However, this is a clear contradiction, as God cannot be both A and B simultaneously. So, according to Spinoza's reasoning, Possible God B does not and cannot exist, because the contradiction caused by the existence of both A and B explains the non-existence of God B. Therefore, God B cannot exist, and, by proxy, a world in which George Bush lost the 2004 election cannot exist.

Leibniz' system of contingency, on the other hand, leaves room for the possibility that there is a possible world in which George Bush lost the 2004 election. To most clearly elucidate his commitment to the truth of our original proposition, it is important we highlight two main parts of his philosophical system. On the one hand, we must understand Leibniz' notion of God's perfection and the complete concept theory; along similar lines, we also must understand his notion of compossibility and possible worlds.

First, let us begin with Leibniz' position on God and the complete concept theory. For Leibniz, there are two types of perceptions that we as thinking things have. First, there are our conscious perceptions (for example, I can perceive a chair at the front of my philosophy class); second, there are our unconscious perceptions, those perceptions which Leibniz asserts we have but we are not conscious of. (Letters to Arnauld) Leibniz' simple substances (or unities) are monads, which are the fundamental building blocks of the entire universe, analogous to the way in which scientists believe atoms to be the fundamental building blocks of matter (Monadology, 1-3). It is important to note, however, that these monads are non-extended substances. " There is nothing in things but simple substances, and in them, perception and appetite," (Letter to De Volder). Furthermore, Leibniz asserts, these monads (or notions) contain the whole sequence of infinite perceptions of the entire universe in the past, present, and future. In other words, the entire scope of the universe in the past, present, and future in contained in the concept of me; my notion contains infinitely conscious and unconscious perceptions, from infinitely many perspectives. In this way, he says, we are all "mirrors of the universe" (Discourse on Metaphysics, 9). However, as we humans are finite beings, there is simply no way we could possibly comprehend the infinitely many perceptions contained in the universe. According to Leibniz, only an infinitely perfect God has the power to comprehend the entire scope of the universe (DM 13).

To further illustrate this claim, Leibniz uses the example of Julius Caesar. What is it in virtue of which Caesar decided to cross the Rubicon? According to Leibniz, contained in the complete notion of Caesar, in the infinitely many universal complexities of the universe in which he exists, is his decision to cross the Rubicon. We humans, as finite beings, cannot assess the complete notion of Caesar's individuality. Only God, as the infinite being, is capable of comprehending with complete clarity all of these infinite perceptions. However, strictly speaking, it is not a necessary truth that Caesar decides to cross the Rubicon. Caesar's complete notion is contingent, as if to say, "If Caesar exists in this world, then he will choose to cross the Rubicon." Leibniz' principle of pre-established harmony states that God created things in such a way that the casual chain of events in the mind and body are perfectly and harmoniously coordinated (New System of Nature). Owing to his system of causal principle, Leibniz would be able to make the claim that in another possible world, God could have harmonized things in such a manner that Caesar existed but did not cross the Rubicon (DM 13). In the same way, God could have harmonized a world in which George Bush existed, but lost the 2004 election. Why, then, does our world exist rather than that one?

Owing to God's perfection, Leibniz says that God chose freely the best possible world from among all the possible worlds (DM 6).What does it mean for Leibniz for this world to be "best"? What criteria constitutes "bestness"? For Leibniz, "bestness" means a simplicity of means and richness of effect, as well as a maximization of metaphysical and moral perfection (DM 5) However, in a sharp contrast to Spinoza, Leibniz asserts that God freely chose this world, rather than Spinoza's claim that this world followed necessarily from God's existence. God, in choosing this specific world, chose the world with the highest maximization of compossible events. That is say, God could have just as well chosen a world in which George Bush lost the 2004 election; however, since the event, "George Bush loses the 2004 election" is not compossible with the events of the world with the highest maximization of compossible events, it does not exist in the best possible world. Therefore, Leibniz certainly seems committed to the thesis that George Bush could have lost the 2004 election, in a possible world which wasn't the best possible world.

Leibniz' system certainly eliminates the rather depressing idea of Spinozian necessity, but does it hold up to scrutiny? On further inspection of his argument for the complete concept theory and contingency, there seem to be two main points of contention that could potentially reduce Leibniz' arguments to the dark depths of necessitarianism.

One question we must ask of Leibniz is this: "So God freely chose the best possible world. What so compelled him to choose the best possible world with the highest maximization of perfection, as opposed to a world with a lower maximization of perfection?" According to his own Principle of Sufficient Reason, there must be a reason for this choice. God's free decree can't simply be a capricious one. Leibniz' response to this objection is, " Yet [it must also be said] that the present state exists because it follows from the nature of God that he should choose the most perfect," (Textes Inedits, 393). If this "free" act follows necessarily from God's nature, then, mustn't it be the case that the choice of this world and thus the chain of events following from this choice are necessary? Leibniz would certainly have a difficult time answering that objection.

Second, when we consider the proposition "George Bush could have lost the 2004 election," it is crucial we answer the question, "What does it mean to be George Bush?" If we apply Leibniz' complete concept theory, we would say that George Bush is the complete notion of a man who was born in Connecticut, raised in Texas, became Texas Governor, won the 2004 Presidential election, etc. It seems that the George Bush we are considering so so complexly specified that a George Bush in a different possible world that lost the 2004 election is not an identical notion. The hypothetical George Bush may be similar in almost every respect to our George Bush, except for that one fact. Therefore, these two notions are not identical.

But, let us suppose that identity across different possible worlds is based on similarity, and not on numerical identity. Leibniz would argue that it is true George Bush could have lost the 2004 election, in a world where an individual almost identical to our George Bush loses the election; or by having not existed, it would be semantically permissible to say "George Bush did not win the 2004 election." Thus, the term "George Bush" becomes a mere reference point for infinitely similar and infinitely possible notions. Is this sufficient grounds for justifying the truth of our original proposition? This, in my judgment, is not a sufficient justification.

Thus, we must ask again, "What does it mean to be George Bush?" When we retrospectively consider the George Bush in our world , then we must define him. The fact that he won the 2004 election defines who George Bush is and how we consider him. In other words, what it means to be George Bush in our world is, among other things, to be the winner of the 2004 Presidential election. Our original proposition, in my judgment, must be assumed to be asked of the George Bush we know. By substituting the definition in place of the proper noun, we essentially are asking, "Could the man, who, among other things, won the 2004 election, lost the 2004 election?" Clearly, to assert the truth of this proposition is to assert a blatant contradiction. Along the same lines, I would think it absurd to ask whether, in a different world, 4 could have been the sum of 2+3 or a triangle been composed of 4 sides. The concepts "4" and "triangle" are defined by "2+2" and "three-sidedness". In much the same manner, " George Bush" cannot be separated from the fact that "He won the 2004 election" because it is his complete concept, in Leibniz' terms.

In conclusion, it seems as though Leibniz' arguments, on closer inspection, are not strong enough to refute necessitarianism. Strict semantical considerations are at the forefront of Leibniz' hypothetical consideration of our proposition, and even our proposition itself. If we are to speak of George Bush in the manner in which our common sense language dictates, then Leibniz has a significant shortcoming in his complete concept theory. It seems the power of Spinozian necessity has metaphorically grabbed Leibniz and thrown him into a well in which he would find it extremely difficult to escape. That is not to say Spinoza's system of causal necessity is entirely free from scrutiny; however, in a matchup between the two Rationalist heavyweights, Spinoza seems to emerge victorious.