Personal Identity & Time
Time and the Medieval World
Arnold A. Smith II thinks there’s always time to consider eternity.
Everyone speaks of time. Time regulates the day and the year. Time robs us of our youth. Time keeps us pressing onward and prevents us from going back. But what is time? Does time actually exist, or is time just an arbitrary social construct? Why is time relevant to our understanding? These questions became key areas of discussion for intellectuals in the medieval period. This article will offer a brief survey of this vast, complex, and fascinating area of medieval debate. Three areas will be considered:
1. The debate over the meaning of time,
2. The problem of time with regard to the creation of the world, and
3. The problem of free will and God’s foreknowledge.
What is Time?
The philosophy of time, like most philosophies of the Middle Ages, begins with the comments of Aristotle. Aristotle’s famous explanation of time as ‘the numberer of things’ comes in Physics 233b. This states that for numbering or counting to take place, there must be a numberer or counter. It seems reasonable enough to assume that if there is no one to count, then there can be no numbers. It seems reasonable, but is problematic, since it assumes numbers cannot exist independent of rational beings.
While this is an interesting problem, one may ask what it has to do with time. At the beginning of the passage, Aristotle writes, “Whether if soul did not exist time would exist or not, is a question that may be fairly asked...” This leads into the problem of numbering, because according to Aristotle’s view, time is the numbering of motion. Each motion is a sequence, a causal chain which extends back to primi mobilis[first cause of motion] but when one begins to number the sequence, a sense of time emerges.
In the thirteenth century, Thomas Aquinas explained this passage by the observation that time and motion were always perceived in relation to one another. One event occurs after another, motion upon motion, and each motion occurs in a different ‘now’. Whenever one moving item is followed by another, and then something in the middle between the two items is perceived, one may determine that time is going on. According to Aquinas, this is because when something like this happens, the mind recognized two distinct ‘nows’ – one before and one after the middle item. In this way events in time are numbered like the before and after in motion. If befores and afters can be numbered, then time is occurring. Time is not itself in motion, but rather is associated with the numbering of motion. This leads Aquinas to redefine Aristotle’s notion of time as “nothing other than the number of motion according to before and after.” However, if this definition is accepted, then it seems time could not have existed before man, because without humanity there would be no one to apply the numbering of motion, and as Aristotle pointed out, if there is motion without soul, there would be only motion, without time.
However, if there was no time prior to man, then what was there? Aristotle answered this question quite adequately: “There would not be time unless there were soul, but only that of which time is an attribute.” So, the subject matter of time, particular things engaged in their particular motions, existed prior to man – but the concept of time could not since no humans existed to conceptualize it. Time is therefore simply the imposition of contrived human order onto the chaos of existing things and their movements.
The Aristotle-Aquinas conception of time was advanced by many medieval thinkers, including the Arab philosopher Avicenna. But there was no clear distinction between time and eternity. As a result, the Fourteenth Century saw much debate on this topic. John Duns Scotus attempted to challenge the Aristotle-Aquinas position with a discussion of ‘potential time’.
Duns Scotus held that time would still exist even without motion: it could measure the ‘universal rest’. According to Duns Scotus, time is not just an arbitrary counting of motion, but rather something independent of motion. Embracing the notion of potential time, Peter Aureole explained that time as a measurement of movement is a human construct: however, prior to that measurement, time simply is. Time exists unnumbered and uncounted as a flow. Aureole indicated that properly speaking, time is not divided into parts but is rather a constant flow. It’s the human mind which divides time into past, present, and future. These are the human constructs – not time itself.
The views espoused by Duns Scotus and Aureole become the starting point for William of Ockham, arguably the most important thinker of the Fourteenth Century. In his Summulae in Libros Physicorum, Ockham writes:
“Time is the measure of movements whose magnitude is not known to us; in fact, it is by time that we recognize the length of a movement... Time is also the measure of temporal things... Finally, in the same way that time measures movements and temporal things, it also measures rest... Those are the principal reasons for which one posits time and for which the knowledge of time is necessary for us.”
So like Duns Scotus and Aureole, Ockham maintains that time measures both movement and rest.
Time and Creation
Many theories emerged to counter the Aristotle-Aquinas position, but why? As with virtually all things medieval, the reason lies in religion. The central problem with Aristotle’s view, skirted by Aquinas and embraced by Avicenna, was that it implied that the world itself must be eternal. It did not come into existence, but rather always has been. This idea did not square with the Biblical account of Creation.
The opposing argument was probably first put forward by the Ninth Century Rabbinite Saadia Gaon ben Joseph, who claimed that the past cannot be eternal, for if it were, an infinite amount of time must have already passed prior to the present point in time – so if time were eternal, we could not be at the point in time we are now. If there were no starting point in eternity we can never go half the length of time, since half of infinity is still infinity, which by definition is non-traversable. Therefore, time and the universe must have had a beginning. According to Saadia this argument demonstrates that God must have created the universe, and it also demonstrates His vast power in that it had to be a creatio ex nihilo.
Saadia argues that “nothing which is subject to time can be eternal, hence not even prime matter.” For time to exist there must be motion, since there must be something to measure (ie some change). With no finite, changing things, there is no time,and so time cannot exist prior to the creation of the universe.
The problem which arises is God. If there is no time prior to creation, then how can God exist in order to bring the universe into creation? The answer is that God, as a perfect, unchanging, eternal being, is not subject to time. Rather, prior to creation, God exists alone in the ‘undifferentiated unsaid’. In simple terms, God is eternal and man is temporal. God exists outside time, and so if ‘in the beginning’ there was God and nothing else, there was no time. There can be time only when God creates and initiates movement.
William of Auvergne, a Bishop of Paris in the Thirteenth Century, argued similarly that the idea of empty time prior to creation depends on a confusion between time and eternity. When one argues that if God existed before the creation of the world then an infinite amount of time would have to be traversed prior to creation, one is mistaking the eternal for the temporal. One thinks in this fashion because one is accustomed to speaking temporally, but to do so is a grave error. Eternity is not like time which needs traversing. William argued that if the world were eternal, then an infinite time would have passed prior to the present moment in time. But, it is impossible to pass through infinite time. Therefore, the world cannot have always existed, but rather must have a beginning in time.
Time and Foreknowledge
One of the central problems surrounding the make-up of time is the question of the past, present, and future. If such concepts reflect reality, then the past should be knowable as history and the present should be knowable as immediate, but what of the future? Human beings generally demand that the future is unknowable since it has not yet been written. However, Christianity demands that God possesses knowledge of all things. Yet if God knows the future, then the future must be predetermined. However, if the future is predetermined, how can mankind have free will? This question plagued philosophers throughout the medieval period.
Although the problem dates back to Aristotle, it was Augustine of Hippo who first placed the problem in a Christian perspective. According to Augustine, the Christian belief in Predestination implies that God has known since the beginning of time who will receive grace and go to Heaven as well as who will be condemned. Augustine insists that everyone has free will, the ability to make their own decisions, including the decision of whether or not to accept grace from God when it is offered. However, if God knows in advance who is saved and who is damned, is the will really free, or is everything determined from the outset with no possibility of change? Augustine’s response is that individuals really do have free will since God does not force or determine a human’s decision; however, God does know what their unforced choice will be.
While Augustine’s response was not phrased in the best possible way, he was attempting to put forth the same response Boethius would make more successfully. In his second commentary on Aristotle’s On Interpretation 9, Boethius examines the role of God in future events. The argument from the first commentary is only concerned with temporal beings, who are unable to know future events; but God is eternal, not temporal, so could God know future events? One would initially think that if God is the all-powerful all-knowing Being, one could not deny Him the power of foreknowledge. The problem is that if God has complete and infallible knowledge of the future, then there’s just one way the future could go, namely the way God foresees it. But if the future is already determined in God’s foreknowledge, rather than advancing the powers of God, one is thereby denying the powers of God. According to Boethius, if God has absolute foreknowledge, it is pointless to pray, try to steer a moral path or do good deeds, since it is already ordained that you will either do these things or not. God cannot intervene to help someone unless the future holds that the person will be helped. God becomes limited in power to aid His creatures. If such is the case, then man does not possess free will, and cannot be either praised or blamed for any of his actions. And just as man can possess no free will, neither can God. Each is capable only of doing that which the future says they will do, with no possibility of change.
So if an act is to be free, even God cannot have foreknowledge of it. It’s a problem of God’s foreknowledge versus free will. In order for God to be God, he must have absolute knowledge of all things, past, present, and future. But if God has knowledge of the future, your actions cannot truly be your own.
In Chapter Five of On The Consolation of Philosophy, Boethius turns his attention to this problem in much more detail. He reminds the reader that only temporal beings can have fore knowledge, but God is not temporal. He is eternal, and so the normal concepts of time do not apply. Instead God exists in an eternity which embraces every moment of time in such a way that every moment is directly present to Him. It only appears to us temporal beings that God has foreknowledge because the human mind thinks in terms of past, present, and future. But consider the following:
It appears from this that God, sitting at the origin of all things, has known the entire future timeline long before it ever occurs. Yet this is not the case, according to Boethius. God exists in eternity, not in time, and so God has knowledge of these events because He witnesses them as they occur simultaneously:
So just as you can have knowledge of free, contingent events in your temporal present, God can have knowledge of free contingent events in His temporal present – which, existing in eternity, comprises our past, present, and future. God only appears to have foreknowledge to us, since we think in temporal terms; but as an eternal being God’s abilities are even greater than foreknowledge. He has granted man free will to make real decisions, for which the individual may be praised or blamed, and has done so without limiting His own omniscient magnificence.
This issue reared its head again in the later Middle Ages when Richard of Lavenham attempted to put the matter into perspective in his De Eventu Futurorum. Richard reasserted the problem that on the one hand man has free will but on the other hand God has divine foreknowledge. He indicated that if one has two dogmas that appear contradictory, then one can solve the problem either by denying one of the dogmas or by showing that the apparent contradiction is not real. To this effect, three solutions were offered to the free will problem. The first solution was to deny that free will exists, which meant accepting fatalism. The second was to deny God’s foreknowledge. This could imply either that God does not know the truth about the future, or that there is no truth about the future for God to know, since it has not yet been decided. To accept either solution is heresy. The only remaining solution was to demonstrate that the two dogmas could be united in a consistent way.
Peter Aureole attempted to use the second solution while avoiding heresy, claiming that God created the world so that the future would be contingent. God knows that any decision made will follow His rules, but the individual following these rules will have free choice. Aureole took the statements “The Antichrist will come” and the “The Antichrist will not come” as an example. The Principle of Bivalence demands that each of these statements is either true or false. So each statement already has a truth value, even though the event has neither occurred nor not occurred yet. Aureole’s point, however, is that neither statement is true or false as of yet. What is true is the disjunction of the two statements: “Either the Antichrist will come or the Antichrist will not come.” As these are the only two possibilities, one will eventually become true while the other will eventually become false. Therefore, the statement “the Antichrist will come or will not come” is a true statement. That is all that can be known at this point. Aureole maintains that while God knows all the truths given, he cannot know if the Antichrist will come, because no truth about the Antichrist’s future decisions yet exists.
William of Ockham countered Aureole’s argument by attempting to make use of Lavenham’s third solution. In Predestination, God’s foreknowledge, and Future Contingents, Ockham indicated that God knows all future contingencies. However, he also indicated that human beings can choose between alternative possibilities. As Ockham explained it, the thing that makes a predictive statement true is an actual, although not yet inevitable, fact about the future. Consider Ockham’s example of Nineveh. When Jonah prophesized about Nineveh, that prophecy should have been seen as a warning: “Unless the citizens of Nineveh repent...” The citizens have the choice to repent or not, and will do so. This was already true at the time of the prophecy, even though it was not yet inevitable. In Ockham’s solution, God knows the future, but only in terms of contingencies. This solution is referred to as ‘Middle Knowledge’; the notion that God knows what every possible free creature could do under any possible set of circumstances.
As you can see, time is very relevant from a religious standpoint. For this reason, the philosophy of time occupies a large amount of space in the medieval corpus, of which this article only scratches the surface.
© Arnold A. Smith II 2007
Arnold Smith teaches philosophy at Kent State University and at Youngstown State University, in Ohio.