however I wanted to lead gradually into the model investigation of fiction, rather to approaches, to approach it to parsley in order to reveal to show you certain from downtown fictional traits, that can be found in the scientific use of fictions and hypothesis, we have to consider it, and in fact we had to choose the starting point, and not only the model point of view, because of the authors who in the seventeenth and eighteenth centuries, express the strongest reservations about the consideration of the real of possibilities, so we had to consider first fiction as an abstraction.
it was more general, it concerns old philosophers of tourist in modern times, but it's not enough, and this is how we don't identified Descartes the importance of a narrative of a diachronic dimension, this dimension must not be lost now， this narrative dimension must not be lost now, at the moment, when the phases of the exhaustion of material forms presents us with the difficult observation of the postulation of necessity, that most animate effective world, and that needs that requires as to approach fiction from the point of view of modalities, that's we are going to do now, furthermore, you're going to discover that these simple postulates the Cartesian and postulate, that matter most successively assume all the forms, all which it is capable, this postulate comes back in the decision of humans of Leibniz on the model status of fiction.
we are I won't talk only about Leibniz, but of course Leibniz is now the most important figures offered to consider, during the first sequence of my work, we had to read Descartes carefully now, we have to deal with Leibniz, for the moment, please pay attention to it, I should simply stipulate that by addressing this aspect of my analysis fiction according to modalities, I am not limiting myself to the case in which fiction maintains its narrative quality.
I suggested in order to stay clear of suggesting that fiction, thereby retains a general doctor, so let's come to two points.
I think that the authentic problem in fact there are several the authentic problems raised by the model interpretation of fiction, do not emerge until we consider them in this relatively in a bullet form, we have to consider fictions as narratives in order to reach the fundamental problems raised by modality, and these problems may be identified in Leibniz, who during this period develops precisely, the most important theory of modality, and in fact the most important theory of modality since Aristotle, I suspect you do not know many things about Leibniz.
so I will give you all you have to know in order to understand those points, but perhaps it will be useful to tell you a few words, because most of you are scientists, so to tell you a few words about Leibniz as a scientist as you knew almost all feels al of philosophers in modern times, are at least concerned with science and most of them are important scientists especially during the seventeenth century, and this is a case for Leibniz, yes I already expounded the law of continuity last time, I guess we remember, but you must know you must， know that Leibniz developed the infinitesimal calculus independently of Newton, there is a and enormous quarrel, about this point in fact we have good reasons to believe that Newton invented calculus first, but the fact is that it is a notation the mathematical notation of Leibniz, that has been widely used from the eighteenth century.
so Leibniz invented these mathematical notation for the infinitesimal calculus, and it has been widely used from the eighteenth century especially in mechanics, it is also worth mentioning, he's incredible Leibniz is an incredible man, he was the first scientists, it is worth mentioning his contributions to the field of mechanical calculators, he made important discoveries concerning mechanical calculators, he added multiplication and division to the calculator invented by Pascal in forty two, that very same century, there is now a link between this and fiction.
butchoose a photo of Pascal calculator, perhaps you have never seen it before, that's it and the name is Pascaline, first making make an equal calculator invented by Pascal, where it only calculated addition and subtraction, Leibniz added multiplication, and division to this machine, that is the reason why Pascaline invented this machine, and that is the reason why his name Pascal as you know was given to a programming language, his name is given to a programming language, because of this machine, and lastly Leibniz is also improved the binary number system.
he did important improvements to this beanery numeric system, of which you know better than me, the importance of groups, so perhaps this will make you take Leibniz seriously, um to understand the remarkable phases of Leibniz on fictions, I have to make some kind of small summary analogous to the one. I gave you on the Descartes, so we're last time it was quite useful, I will do the same for Leibniz, to realize the important part, play by Leibniz in a model approach to fiction, I will though summarize some facets of his very demanding conception of rationality.
first point, the most important decisions the most important decision lies probably in an absolutely general definition of truth, Leibniz is giving us an absolutely according to him absolutely general definition of truth, concept id as the inclusion of the predicate into the subject, for each proposition truth means the inclusion of the predicate into the subject, let's be more precise, in case, so the first decision and I think it's important to know, this whatever you are studying.
I will do it five points.
first the definition of truth by the inclusion of the predicate in the subject, and he's distinguishing two kinds of truth, two kinds, in case of necessary truth, for instance mathematical truth pretty gates are in a finite number, pretty gates are in a finite number, and it is possible at least by right, it is possible at least by by right to demonstrate these truth by reducing the proposition to identity, this is a reduce a finite number of three decades, and it is possible to demonstrate by right it is possible to demonstrate these truth, true a reduction to identity, the problem, and the difficulty is calm with contingent truth, this is going to be of far more far more difficult truth necessary.
I won't speak about necessary truth and contingent truth, they are irreducible to mayor identity according to Leibniz, contingent truth are irreducible to mayor identity, and when the express, pay attention please, when the express the notions of evens, that occur in this world, there are contingent truth about this world, for instance that Caesar cross the Rubicon River, that is a contingent truth about this world all.
in fact, that the any level of nature is so this is also a contingent truth, laws of nature according to light needs are contingent truth, so concerning the events in this world, the notions of the events that will cure in this world, or the notions of existing beings of existing creatures, pretty gates are in infinity in finite member, so for contingent truth it is impossible to reduce them to mayor identity, and predicate are in an in finite number, why are pretty gates and in finite number, when we deal with truth about evens or existing beings in this world, that is the second point, perhaps you know about it, because the motions corresponding to beings existing beings these notions express their integration in the whole world.
this notion, these notions express the integrations of these beings in the whole world, let's take two examples, that Leibniz there is often using, the notion of Adam, the first man the notion of Adam or the notion of Caesar, they contain an infinite number of pretty gates, which did you mean not only their actions, the notions of those beings determine age their actions to be clear, the notion of Adam indicates that he won't commit the original scene, this isn't his notion this notion indicates he would commit the original sin.
and the motion of Caesar that he would cross the Rubicon River, that he would cross the Rubicon River, before entering Rome, the predicate do not only determine their actions, so pretty gates are about all the events, all the events either in the best, all means of future, which in the created world, they belong, is that the notion I resumed the notion of Adams Caesar or you the determine your actions, committing the original seen concerning Adam, but also all the events that a cure in the world they be longer.
yes please a lower scale of the second, for the new measure after added oh, it is if he is the first man in the bible, the first man created by god and he committed the original scene well, this is only an example, that's it what Caesar, it's quite famous even in China, I guess you should have told me, before you are not used to it.
but it doesn't matter in fact you could choose Confucius, it would also be true according to Leibniz , so you see it's very original, of course some truth may be considered about Jews figures, it is true that Caesar crossed the Rubicon River, but if we talking about truth according to Leibniz, then we have to then we have to consider that a certain notion is including the pretty gates, we are considering for instance the notion of Caesar, includes this predicate crossing the Rubicon River, this is the very condition in order to talk of a truth about them, but concerning existing beings, they're all and infinite number of pretty gates and of course you cannot reduce nobody not even god, can reduce to truth to make identity whereas it is possible, for necessary truth, according to Leibniz .
so the is you knew philosophers, there are always I don't know in China,but in western Europe there are always inventing names, always this is not the most important, but when Leibniz is considering the notion of an existing being, a notion which I repeat contains and in finite number of predicate, he's talking about complete notion, an existing being has a complete notion.
second point the complete notion and the determine everything that happens to seize individual, and besides in this notion everything, that to choose in the world is expressed also is also expressed.
third point therefore is completely determined, the Leibniz and world is completely determined and for instance, it is not possible to assert seriously, it is not possible to assert, that Adam might not have committed sin, it has no sense, it is impossible to set that Adam might help might have not committed sin, all that Caesar might not have crossed the Rubicon, because the world is entirely determined, we can't have said that Adam might not have committee that Caesar might have not crossed the Rubicon, there is an important consequence, this means that there is no meaning according to Leibniz, there is no meaning in taking a purely isolated individual.
you know in account, this has no meaning it has no serious meaning to consider an individual such as Adam Caesar and so on, in account own by isolating in completely it has no meaning.
so for instance the notion of and Adam none sinner would have been great, and that Adam none sinner, the notions, is abstract and not rather them to consider a true being, we're not talking when we're talking about another known sinner, we are not talking about the true meaning.
he has another expression to formerly that this notion will be the notion of vague Adam, but the vague atom is not a true being, that what happens when you are considering an individual by obstructing him from his world.
so the third point determination of the world and of only notions, everybody can see that you can read it, determination vertices, and at the opposite you will remember this, the vague atom, debate Adam is not a true being, so if you have paid attention to all what I said till now, you must have a very big problem, very big problem, why because remember here we are considered considering contingent truth, we are talking about of contingent truth, this is a problem, the paradox the obvious paradox lies in the service, that's the proposition, so it's propositions describing the real world, the real evidence, the real beings those propositions, I suppose to be contingent propositions of course there is a paradox in it.
, it has no sense to imagine an atom that would not have committed seen, so it means that to some extent we can't give a sense to the opposite proposition of these Adam committed seen, but if we can't give a sense to the opposite proposition, then it's a necessary proposition, but now, the problem is everything, we are talking about contingent propositions, I know this is unbearable, this is very hard, this is a cruel by me, but we will observe a short break, before I give you the solution let's make a short break.
