Chapter 20 of book II of John Locke’s An Essay Concerning Human Understanding, titled ‘Of Modes of Pleasure and Pain’ is the most extensive discussion of emotions available in Locke’s corpus. Likewise, Nouveaux essais sur l’entedement humain, II, xx, together with the following chapter xxi remains the chief source of Leibniz’s views of emotions. They offer a very interesting and captivating discussion of moral philosophy and good life. The chapter provides also a great platform to study Leibniz’s argumentative techniques and (...) the differences between the philosophers in general. Locke strives to explain the emotions with a single, unifying notion of uneasiness while Leibniz’s view of the mind is much more complex and he finds more unique ways of explaining different emotions. My paper focuses on Leibniz’s critique of Lockean uneasiness as an explanans for emotions. He views uneasiness as a unavoidable part of all our mental states and therefore it is not sufficient to explain passions or moral wrong-doing of men. I will discuss such passions as love, joy, sorrow, hope, fear, despair, anger, envy and shame and consider Locke’s possible response to Leibniz’s critique. (shrink)

Descartes argued that the passions of the soul were immediately felt in the body, as the animal spirits, affected by the movement of the pineal gland, spread through the body. In Leibniz the effect of emotions in the body is a different question as he did not allow the direct interaction between the mind and the body, although maintaining a psychophysical parallelism between them. -/- In general, he avoids discussing emotions in bodily terms, saying that general inclinations, passions, pleasures and (...) pains belong only to the mind or to the soul (NE II, xxi, §72). He is also keen to point out that our passions derive mostly from our bodies. However, like Spinoza (Ethics III, prop. XI, Scholium) he thought that some emotions such as joy can produce pleasures which can be described also in bodily terms. For example, in a short memoir Felicity he says that music can be a pleasure for the ears and symmetry can be a pleasure for the eyes. These more intellectual emotions are actions in the sense that they represent perfection emanating from their source, the absolutely perfect being, that is, God. The feeling of perfection may produce a state of well-being which concerns both the soul and the body. -/- In my paper I will trace instances of Leibniz’s remarks on how these kind of emotions affect the body. I will also discuss the different ways the body gives rise to passions in the soul. My primary source is Nouveaux essais, book II, chapter xx and xxi, but I will also discuss various other writings by Leibniz. (shrink)

In New Essays on Human Understanding, book II, chapter xxi Leibniz presents an interesting picture of the human mind as not only populated by perceptions, volitions and appetitions, but also by endeavours. The endeavours in question can be divided to entelechy and effort; Leibniz calls entelechy as primitive active forces and efforts as derivative forces. The entelechy, understood as primitive active force is to be equated with a substantial form, as Leibniz says: “When an entelechy – i.e. a primary or (...) substantial endeavour – is accompanied by perception, it is a soul” (NE II, xxi, §1; RB, 170). What about efforts, then? One is certainly the will. In NE, II, xxi, §5 Leibniz argues that volition is the effort (conatus) to move towards what one finds good and away from what one finds bad and that this endeavor arises from the perceptions we are aware of. As an endeavour results in action unless it is prevented, from will (which is always directed to the good) and power together follows action. However, this is not so simple. Leibniz argues that there is also a second class of efforts: “There are other efforts, arising from insensible perceptions, which we are not aware of; I prefer to call these ‘appetitions’ rather than volitions” (NE II, xxi, §5; RB, 173). Although there are appetitions of which one can be aware, usually these appetitions arise from the insensible petite perceptions and are consequently affecting us subconsciously. Now, although all minute perceptions are confused perceptions, they are always related to pleasure and displeasure and also to perfection and imperfection. From this follows that there can be different efforts present in the soul at the same time: the will which is directed to apperceived good and several separate appetitions which lead to different goals, both to those which bring about perfection and pleasure of the mind (joy) and those which bring about displeasure and imperfection (sorrow). These efforts are not only in conflict with each other but may also be in conflict with entelechy. A typical case is perceiving a sensual pleasure. Our entelechy which is always directed to final causes (perfection) may be in conflict with several different appetitions which are related in different ways to the sensual pleasure in question. If our understanding is developed enough, our will resists the temptation posed by the pleasure (agreeing with entelechy), but if the temptation is too strong, the appetitions outweigh the will and the resulting action bring about imperfection and sorrow as it is related to imperfection. In this paper I will argue that deliberation in the human soul is a battle of different endeavors described above: the entelechy in the soul strives according to its law-of-the-series towards its telos (perfection) and the will accompanies it by being automatically directed to the good. This thrust towards the apparent good is aided or hindered by the appetitions which can be thought as derivative forces in the Leibnizian dynamics. Depending on whether the predominant appetitions are related to good or bad desires, the deliberation succeeds or fails in achieving the real good which is the goal of human deliberation. The successs can be facilitated beforehand by developing our understanding so that we are less easily swept away by the derivative forces (NE II, xxi, §19). A central role in this task is played by strong willing. As Martha Bolton has noted in her recent paper, an essential feature of the basic, standing endeavors is that they are continuous – although the power balance in the soul changes from moment to moment, something lingers from our previous volitions. That is why Leibniz argues that we pave way for the future deliberations by our previous voluntary actions (NE II, xxi, §23). In contrast, the appetitions are temporary, fliegende Gedanken as Leibniz says in NE II, xxi, §12. Therefore there is a constant, always changing power balance between two kinds of endeavors in the soul: primitive active force versus derivative forces. I will argue that the behavior of the forces in the soul can be understood with a vectorial model which is related to Leibniz’s early ideas of calculus of variations and which was anticipated by Arnauld and Nicole’s Port-Royal Logic. The central idea in the model is that the options are in tension towards each other and the ratio between them at each moment determines the consequent outcome. The proper relationship between the endeavors is not a simple balance, two options which exhaust each other, but a case where different efforts complement each other: “Since the final result is determined by how things weigh against one another, I should think it could happen that he most pressing disquiet did not prevail; for even If it prevailed over each of the contrary endeavours taken singly, it may be outweighed by all of them together.” Leibniz continues : “Everything which then impinges on us weighs in the balance and contributes to determining a resultant direction, almost as in mechanics” (NE II, xxi, §40; RB, 193). The different endeavors can be understood as vectors leading to different directions and the end result is a certain direction that deliberation takes. The dynamical tension between the different endeavors presents a situation where everything affects everything and the following direction, the resulting volition follows more or less automatically. In Theodicy, §325 Leibniz describes the deliberation as follows: “One might, instead of the balance, compare the soul with a force that puts forth an effort on various sides simultaneously, but which acts only at the spot where action is easiest or there is least resistance” (Huggard, 322) This kind of dynamical tension can be understood in terms of the calculus of variations where there are several possible variations available but where the dynamics of the situation results in the decision taking the “easiest” route which is more or less objectively good depending on the level of the deliberator’s understanding. In his comments to Bayle’s note L of “Rorarius” Leibniz says: “The soul, even though it has no parts, has within it, because of the multitude of representations of external things, or rather because of the representation of the universe lodged within it by the creator, a great number, or rather an infinite number, of variations (Woolhouse & Francks (ed.), ‘New System’ and Associated Texts, 101). This kind of deliberation is comparable to God’s choice of the best world with the difference that God’s understanding is infinite which again results in the fact that the choice is the best possible. Whereas in nature the easiest route taken is always optimal as nature is God’s creation, in men the goodness or badness of men’s actions is dependent on their state of wisdom, that is, how developed their understanding is. The more wise men are, the more metaphysical goodness or perfection follows from their actions. (shrink)

In his early lecture note Versuch einiger Betrachtungen über den Optimismus (1759) a young supporter of metaphysical optimism called Immanuel Kant tested the Leibnizian optimism by posing some counter-arguments against it only to falsify them. His counter-arguments were very inventive and they feature often in modern scholarship on Leibniz. In this paper I will present Kant’s main arguments and evaluate them. I will argue that Kant’s understanding on Leibnizian optimism is little misguided and for this reason his own positive counter-argument (...) despite its ingeniousness is problematic. His second solution to the problem is comparable to the doctrine of metaphysical optimism, but fails also for the same reason as the first one. -/- . (shrink)

Keskityn tässä esitelmässä varhaismodernistisen filosofian unia koskeviin näkemyksiin, johon monet myöhemmät teoriat unien ja muistin suhteesta perustuvat. Lähtökohtani on Descartesin ja Hobbesin välinen väittely unien luonteesta, mutta käsittelen myös monia muita näkemyksiä aiheesta.

One of the features of John Locke’s moral philosophy is the idea that morality is based on our beliefs concerning the future good. In An Essay Concerning Human Understanding II, xxi, §70, Locke argues that we have to decide between the probability of afterlife and our present temptations. In itself, this kind of decision model is not rare in Early Modern philosophy. Blaise Pascal’s Wager is a famous example of a similar idea of balancing between available options which Marcelo Dascal (...) has discussed in his important 2005 article “The Balance of Reason”. -/- Leibniz, however, was not always satisfied with this kind of simple balancing. In his commentary to Locke’s Essay, Nouveaux essais sur l’entendement humain, II, xxi, §66, he presented an alternative model which is based on an idea of plural, mutually conflicting inclinations. This kind of model, called as vectorial theory of rational decision by Simo Knuuttila, fits well with Leibniz’s theory of the soul where volitions are formed as a kind of compromise between different inclinations to different goods. -/- I will present these two models and show how they illustrate the practical rationality of Locke and Leibniz and how their moral philosophies differ, although being similar in certain respects. The topics include Leibniz’s criticism of Lockean hedonism and the discussion of akratic behaviour in II, xxi of Essay and Nouveaux essais. (shrink)

In this paper I will discuss the doctrine of substance which emerges from Leibniz’s unpublished early memoir De affectibus of 1679. The memoir marks a new stage in Leibniz’s views of the mind. The motivation for this change can be found in Leibniz’s rejection of the Cartesian theory of passion and action in the 1670s. His early Aristotelianism and some features of Cartesianism persisted to which Leibniz added influences from Hobbes and Spinoza. His nascent dynamical concept of substance is seemingly (...) a combination of old and fresh influences, representing a characteristically eclectic approach, but I will argue that the influence of Hobbes is especially important in the memoir. To do that, I will examine Leibniz’s development in the 1670s up to the De affectibus and consider the nature of affects in the memoir, especially the first affect which starts the thought sequence. This first affect of pleasure or pain is the key to Leibniz’s theory of active substances and in this way to the whole of Leibniz’s moral psychology and ethical metaphysics. (shrink)

Käsittelen tässä artikkelissa Leibnizin käsitystä kuolemasta, jota ei tarkkaan ottaen ole olemassa. Kuoleminen on Leibnizin mukaan vain tila, jossa havaintomme eivät nouse tarkoiksi ja vaivumme ikäänkuin elottoman luonnon tasolle.

Artikkelissaan ”The Balance of Reason” Marcelo Dascal on osoittanut, että metafora syiden punnitsemisesta järjen vaa’assa on yleinen Leibnizin kirjoituksissa ja sitä on pidettävä hänen yleisenä järkeilyn metodinaan tilanteissa, joissa ei voida suorittaa täydellistä loogista analyysiä. Keskustelen tässä esitelmässä tuosta metaforasta ja ehdotan Jaakko Hintikan ja Simo Knuuttilan aiempien esityksien pohjalle rakentaen, että käsityksissään ihmisen praktisesta rationaalisuudesta Leibniz sovelsi myös toista melko tuntemattomaksi jäänyttä heuristista päätöksentekomallia, joka liittyy hänen työhönsä luonnonfilosofiassa ja mielenfilosofiassa, ja jota hän sovelsi tapauksissa joissa päätökseen vaikuttavat arvot (...) ovat toisiaan täydentäviä. Tämä moniarvoisuuden huomioon ottava malli edustaa uudenlaista ja modernia ajattelua moraalifilosofian historiassa. (shrink)

Kertomus René Descartesin kuolemasta / An account of the Death of René Descartes.

Human deliberation is a complicated and a difficult process. When forming moral judgement, various reasons inclinate the agent without necessitating him or her and the final result is more or less a compromise between these different spurs for action. Choosing right requires clear mind, good habits and strength of will. However, by a kind of self-manipulation moral development is possible. In my presentation, I shall discuss the forming of moral judgement in the intellect, consider the role of the passions in (...) deliberation and discuss how moral self-improvement takes place according to Leibniz in Nouveaux essais and Animadversiones in partem generalem Principiorum Cartesianorum. (shrink)

In §18 of Principles of Nature and Grace, Based on Reason, Leibniz says: ”Thus our happiness will never consist, and must never consist, in complete joy, in which nothing is left to desire, and which would dull our mind, but must consist in a perpetual progress to new pleasures and new perfections.” -/- This passage is typical in Leibniz’s Nachlass. Universal perfection creates in us joy or pleasure of the mind and its source is our creator, God. When this joy (...) is constant, we reach happiness and wisdom which is a kind of standing state of virtue, readiness to practice charity in the best of all possible worlds. However, it also indicates that our knowledge is never perfect. Perfecting our knowledge is a never-ending process which gives us joy in itself and motivates us to act in imitation of God. In this way some passions advance our knowledge and we can create ourselves a passionate habit of knowing more about the world and its perfection. In this paper I try to see this process of self-perfection from a cognitive rather than ethical point of view. While it is clear that in the final stage of wisdom we act mostly on our volitions which are founded on clear and distinct perceptions, it is less clear what cognitive status is to be attributed to our initial perceptions of perfection, our emotions and finally, the intellectual emotions which lead us to perfection and God. I will also reflect the role of the minute perceptions in our struggle for happiness. My argument is that a central cognitive role in Leibniz’s views on self-perfection is held by clear, but confused perfections which are subjective, undemonstrable impressions, shades, feelings. Therefore our ethical action is largely founded on passing, minute feelings rather than on deliberated conscious volitions, although the goal in Leibniz’s moral theory is to change this fact. -/- My discussion is founded on several texts from Leibniz’s later philosophy, such as the discussion following from New System of the Nature and the Communication of Substances of 1695, Leibniz’s letter to Queen Sophie Charlotte of 1702 (also known as On What is Independent in Sense and Matter), New Essays on Human Understanding (1704), Theodicy (1710) and naturally Leibniz’s most important epistemological text, Meditations of Truth, Knowledge and Ideas (1684). (shrink)

will give an overview of the fascinating communication between G. W. Leibniz and Pierre Bayle on pre-established harmony and sudden change in the soul which started from Bayle’s footnote H to the article “Rorarius” in his Dictionnaire historique et critique (1697) and ended in 1706 with Bayle’s death. I will compare the views presented in the communication to Leibniz’s reflections on the soul in his partly concurrent Nouveaux essais sur l’entendement humain (1704) and argue that many topics in the communication (...) with Bayle are discussed with more details in Nouveaux essais. I also argue that the communication helped Leibniz to respond to Locke’s views concerning uneasiness in An Essay Concerning Human Understanding, II, xxi. Bayle himself, however, was not able to completely understand Leibniz’s views on spontaneity as he was unaware of the contents of the Nouveaux essais, especially the systematic role of petites perceptions in Leibniz’s philosophy of mind. I will also reflect on whether the controversy could have ended in agreement if it would have continued longer. (shrink)

Kertomus Leibnizin kuolemasta / An account of the death of Leibniz.

Leibniz frequently argued that reasons are to be weighed against each other as in a pair of scales, as Professor Marcelo Dascal has shown in his article "The Balance of Reason." In this kind of weighing it is not necessary to reach demonstrative certainty – one need only judge whether the reasons weigh more on behalf of one or the other option However, a different kind of account about rational decision-making can be found in some of Leibniz's writings. In his (...) article "Was Leibniz's Deity an Akrates?" Professor Jaakko Hintikka has argued that Leibniz developed a new vectorial model for rational decisions which is better suited to complicated decisions, where values are complementary to each other. This model, related closely to his work in metaphysics and the philosophy of mind, is a heuristic device which helps in finding rational combinations - and in an ideal case an optimum - between plural inclinations to the good. I shall argue that Leibniz applies more or less implicitly both of these models in his practical rationality. In simple situations he applied the pair of scales model and in more complicated situations he applied the vectorial model. (shrink)

G. W. Leibniz famously proclaimed that this is the best of all possible worlds. One of the properties of the best world is its increasing perfection. He gave a prominent role in his discussion of emotions to hope which is related to intellectual activity such as curiosity and courage which again is essential for the practice of science and promoting the common good. Leibniz regarded hope as a process where minute perceptions in the mind, that is, unconscious promises or signs (...) of a future pleasure of the mind or joy may accumulate to an expectation which we became aware of, the passion of hope. Related to a moral instinct of striving for joy and avoiding sorrow, hope motivates us to promote perfection which produces joy in us and eventually leads to happiness. (shrink)

Leeuwenhoekin kokeilut mikroskoopilla 1600-luvun lopulla olivat G. W. Leibnizille suuri innoituksen lähde. Monadologia-teoksessaan Leibniz hehkutti keksinnön merkitystä ja antoi ymmärtää, että sillä löydetyt pikkuruiset eliöt todistivat hänen metafyysisen pluralisminsa oikeaksi. Hänen mukaansa "huomataan, että pienimmässäkin osasessa ainetta on kokonainen elävien olioiden, eläinten, entelekhioiden ja sielujen maailma." Näin Leibnizin ajatus elämän jatkumosta sai uutta pontta. -/- Keksinnön vaikutus näkyy myös Leibnizin teoksessa Uusia esseitä inhimillisestä ymmärryksestä, jossa hän esittelee pienet perseptiot, joita voidaan pitää tietoteoreettisena vastineena pieneliöille. -/- Tarkastelen esitelmässäni Leibnizin reaktioita (...) mikroskooppiin ja sen antamaan uuteen kuvaan elämästä ja keskustelen joistakin Leibnizin filosofian piirteistä, joissa voidaan huomata uuden keksinnön vaikutusta. -/- An article on the continuum of life in Leibniz's philosophy. (shrink)

This paper discusses the topic of weakenss of the will or akrasia in Leibniz, especially in the context of Nouveaux essais sur l'entendement humain. I argue that Leibniz can be seen as supporting both the weak and the strong forms of akrasia in book II of the work.

Julkaisematta jääneessä muistiossaan Mietteitä oikeuden yleiskäsitteestä (1702-1703?) G. W. Leibniz muotoilee uudelleen Platonin Euthyfron-dialogissa esitetyn kuuluisan kysymyksen. Hän kirjoittaa: ”Myönnetään, että kaikki mitä Jumala tahtoo, on hyvää ja oikein. Sen sijaan kysytään, onko se hyvää ja oikein siksi että Jumala niin tahtoo, vai tahtooko Jumala sitä koska se on hyvää ja oikein. Eli kysytään, onko hyvyys tai oikeus jotakin mielivaltaista, vai koostuvatko ne asioiden luonnetta koskevista välttämättömistä ja ikuisista totuuksista, kuten luvut ja suhteet.” Universaaleja, ikuisia totuuksia puolustava filosofi ei voi (...) hyväksyä ensin mainittua vaihtoehtoa. Hänen mukaansa ”Se toden totta tuhoaisi Jumalan oikeudenmukaisuuden. Sillä miksi ylistäisimme häntä oikeudenmukaisista teoista, jos oikeudenmukaisuuden käsite ei hänen tapauksessaan lisää mitään teon käsitteeseen? Ja sanonta stat pro ratione voluntas, minun tahtoni käyköön perusteesta, on todella tyrannin motto.” Leibnizin kritiikki on suunnattu erityisesti hänen aikalaisiaan René Descartesia, Thomas Hobbesia ja Samuel Pufendorfia vastaan. Hän ei voi hyväksyä näkemystä, jonka mukaan oikeudenmukaisuuden mitta on vain Jumalan tahto. Perustan on löydyttävä ikuisista totuuksista, jotka ovat myös Jumalan oikeudenmukaisuuden standardi. Erityisen kuuluisaksi tuli Leibnizin kritiikki Pufendorfin näkemyksiä kohtaan, sillä Pufendorfin laajalle levinneen teoksen De officio hominis et civis ranskalaisen laitoksen neljännen painoksen toimittaja Barbeyrac liitti siihen Leibnizin kiistakirjoituksen, joka tunnetaan lyhyellä nimellä Monita (Epistola viri excellentissimi ad amicum qua monita quaedam ad principia Pufendorfiani operis de officio hominis et civis continentur, 1706) ja puolusti Pufendorfia Leibnizia vastaan. Leibnizin onnistui kuitenkin ilmeisesti osoittaa eräs heikkous Pufendorfin näkemyksissä, jota Barbeyrac ei pystynyt sivuuttamaan: tämän mukaan Jumala on saman aikaan sekä ylin tuomari että lakien laatija. Siten Leibnizin näkökulmasta Jumala on tyranni – hänen tahtonsa on oikeuden ja etiikan mitta ja koska hän on kaikkivaltias, hän voi pakottaa ihmiset noudattamaan sellaista oikeudenmukaisuutta, joka on hänen mieleistään. Koska Jumalan yläpuolella ei ole Pufendorfin mukaan mitään, hän voi toimia aivan mielivaltaisesti. Leibnizin kritiikki kiteytyy Pufendorfin epäselvään erotteluun ulkoisen ja sisäisen velvollisuuden välillä, joka jättää hänen näkemyksensä arvoitukselliseksi. Tutkiskelen tässä esitelmässä oliko Leibnzin kritiikki johdonmukainen ja oikeutettu. Onko Pufendorfin näkemyksissä heikkous, jota hän ei itse huomannut? Vertailen myös asiaa koskevia eri kommentaareja (mm. Kari Saastamoinen, Petter Korkman, Fiametta Palladini) ja arvioin Leibnizin kritiikin reseptiota Pufendorf-tutkimuksessa. (shrink)

The topic of disinterested love became fashionable in 1697 due to the famous amour pur dispute between Fénelon (1651-1715) and Bossuet (1627-1704). It soon attracted the attention of Electress Sophie of Hanover (1630-1714) and she asked for an opinion about the dispute from her trusted friend and correspondent, the Hanoverian councilor Gottfried Wilhelm Leibniz (1646-1716). This gave Leibniz an opportunity to present his views on the matter, which he had developed earlier in his career (for example, in Elementa juris naturalis (...) of 1671 and Codex iuris gentium of 1693). In his 1697 letter to Sophie he did not explicitly take sides in the dispute, but formulated his own views on the topic in a theological manner, aiming to provide an account of disinterested love which would surpass the doctrines of both French theologians. In addition to presenting Leibniz’ early views on disinterested love and examining this alternative formulation of his views on love, I will show that after the letter Leibniz gave this alternative perspective up and returned to his earlier, more philosophical views on the topic, which suggests that he regarded them to be superior to the theological version, where the virtue of charity was related to the virtue of hope. (shrink)

This paper discusses Leibniz's views on apperception, especially in the context of this pseudo-dialogue with John Locke, An Essay Concerning Human Understanding. I emphasize the role of attention in the process of becoming conscious of a perception.

G. W. Leibnizin mielenfilosofiassa ymmärrykselle on jatkuvasti läsnä erilaisia taipumuksia erilaisiin päämääriin. Nämä taipumukset tai syyt toimia jollakin tavoin saattavat perustua selviin ja tarkkoihin havaintoihin ja olla tiedostettuja ennakkotahtomuksia. Näiden lisäksi mielessämme on epälukuinen määrä epäselviin havaintoihin perustuvia tiedostamattomia ja hetkittäisiä passioita, oikkuja tai hurahduksia. Kun henkilö ryhtyy harkitsemaan toimintaansa, nämä erilaiset taipumukset ja ennakkotahtomukset alkavat ottaa mittaa toisistaan. Prosessin tuloksena on lopullinen tahtomus tai riittävä syy. Kun ymmärrys on muodostanut suosituksen, tahto seuraa Leibnizin mukaan sitä ja toteuttaa ao. toiminnan. (...) -/- Ideaalitapauksessa ymmärryksen suositus on optimi näistä eri suuntiin johtavista syistä. Tavallisesti kyseessä on kuitenkin kompromissi, joka johtuu epäselvien havaintojen häiritsevästä vaikutuksesta harkintaan. Mitä paremmin ymmärrys toimii ja mitä tarkempia havainnot ovat, sen parempi on ymmärryksen toimintasuositus ja sita vahvemmalla ovat selvän ja tarkan joukkue epäselvän joukkuetta vastaan. Kuvaan esitelmässäni ylläolevan tilanteen ja tarkastelen tapoja, jolla agentti voi vaikuttaa toimintaansa. Vertailen myös pikaisesti Hobbesin ja Leibnizin näkemyksiä riittävästä syystä. (shrink)

Artikkeli Leibnizin ja Hobbesin harkinnasta ja tahdosta / An article on the views of deliberation and willing in Leibniz and Hobbes.

In this study I discuss G. W. Leibniz's (1646-1716) views on rational decision-making from the standpoint of both God and man. The Divine decision takes place within creation, as God freely chooses the best from an infinite number of possible worlds. While God's choice is based on absolutely certain knowledge, human decisions on practical matters are mostly based on uncertain knowledge. However, in many respects they could be regarded as analogous in more complicated situations. In addition to giving an overview (...) of the divine decision-making and discussing critically the criteria God favours in his choice, I provide an account of Leibniz's views on human deliberation, which includes some new ideas. One of these concerns is the importance of estimating probabilities – in making decisions one estimates both the goodness of the act itself and its consequences as far as the desired good is concerned. Another idea is related to the plurality of goods in complicated decisions and the competition this may provoke. Thirdly, heuristic models are used to sketch situations under deliberation in order to help in making the decision. Combining the views of Marcelo Dascal, Jaakko Hintikka and Simo Knuuttila, I argue that Leibniz applied two kinds of models of rational decision-making to practical controversies, often without explicating the details. The more simple, traditional pair of scales model is best suited to cases in which one has to decide for or against some option, or to distribute goods among parties and strive for a compromise. What may be of more help in more complicated deliberations is the novel vectorial model, which is an instance of the general mathematical doctrine of the calculus of variations. To illustrate this distinction, I discuss some cases in which he apparently applied these models in different kinds of situation. These examples support the view that the models had a systematic value in his theory of practical rationality. (shrink)

I attempt to appy Leibniz's vectorial model of rational decision-making to a memoir on church reunion.