Nicholas Rescher

One of the most notable theses of McTaggart’s system is his doctrine of logical determinism, the contention that—on grounds of fundamental logical principle—everything in the world must of necessity be just exactly as it is, that nothing could possibly differ in any particular from its actual condition. McTaggart holds that given that any substance in the world is what it in fact is, every substance must be just as is. And so “all that exists, both substances and [their] characteristics, are held together in one system of extrinsic determination”. For “every fact about every other substance [different from the universe itself] extrinsically determines every fact about the universe, and…every fact about the universe extrinsically determines every fact about every other substance”. And, therefore, “the supposition that anything should be different from what it is, therefore, is one we have no right to make”. Things are bound up in one vast network of mutual necessitation.

The metaphilosophical tendency of philosophical idealism inclines towards a view of philosophy itself that locates the goal of this enterprise in the construction of a cogent and comprehensive account of the nature and grounding human mind's experience of its world. And the coherentism to which idealism in general inclines is operative here as well. However, such a view of philosophizing's mission soon constrains the project to confront the implications of the complexity of human experience-its immense diversity and variability. Conflicting tendencies and tensions are present throughout. Any attempt at the rational systematization of experience is bound to come up against its inner stresses and strains that brings an aporetic complexity to the fore. Against the background of this general line of thought, I have argued in earlier publications for three interconnected theses regarding philosophical methodology

The ancient problem of mind-matter relationship still has traction. Cartesian dualism created a seemingly impossible divide here. But with the decline of mechanism on the matter sides the issue of trans-categorical causality no larger secured insurmountable. However, with a more open concept of causality in view, there is no reason to think that the causality at issue here is a one way street from matter to mind. The mind-brain can be seen as a unified hermeneutical engine that permits of two-way operation. Mark Twain asked “When the body is drunk, does the mind stay sober?” But one may just as well ask “When the mind says ‘Write!,’ does the hand remain immobile?”

In der Zeit von 1712-1714 verbrachte Leibniz fast zwei Jahre in Wien. Vorgeblich beschäftigte er sich während dieser Zeit mit der Materialsuche für die Historia Domus des Welfenhauses und führte nebenbei zu dessen Gunsten diplomatische Gespräche. Tatsachlich war er damit beschäftigt, für die Gründung einer Sozietät oder Akademie der Wissenschaften unter seiner Führung als Ausgleich für die stetige Reduktion seines Prasidentenamtes an der Berliner Akademie zu werben. Allerdings führten die Kontakte, die er knüpfte, zum Entstehen der wichtigsten vergleichenden Überblicke seiner Philosophic der „Principia philosophiae“, die unter dem Titel „Monadologie“ bekannt geworden ist, und der „Principes de la nature et de la grace“. Zusammenfassend wirft Leibniz' Aktivität in dieser Phase ein aufschlußreiches Licht auf seinen modus operandi als Gelehrter, Diplomat und Höfling

Unter den Stichwörtern 'palingenesis' und apokatastasis studierte Leibniz die Grenzen menschlichen Wissens. Er betonte dabei den Unterschied zwischen unserem menschlichen Wissen, welches begrenzt ist, sowohl im Umfang als auch in seinen Einzelheiten, und dem Wissen Gottes, welches in beiderlei Hinsicht grenzenlos ist. Leibniz betrachtete eine korrekte Einschätzung dieses Umstandes als wesentlich für die Metaphysik. Denn es bedeutet, dass unser theoretisches Wissen nicht in der Lage ist, mit den Einzelheiten der Welt Schritt zu halten - und nicht allein mit ihren tatsächlichen Einzelheiten, sondern auch mit den beobachteten Einzelheiten. Dies bedeutet aber, dass ein gewisser Grad an Verworrenheit unausweichlich für unser perzeptuales und konzeptuales Wissen über die Realität sein wird

It would be unproblematically correct to say "the laws of Pennsylvania have it that a person is eligible to vote at age eighteen." But whether someone is actually mature enough to exercise his electoral franchise appropriately will very much depend on the individual. In setting the voting age by fiat, Society leaps in where Nature fears to tread. Many quantities that figure importantly in shaping our conduct of affairs are not specified by nature but are artifacts of human contrivance. At what age, for example, is a person old enough to marry, drink alcoholic beverages responsibly, handle fireworks safely, manage his own property, enter into contracts, see a violent movie, serve on a jury, or hold a public office? These are not quantities writ large in nature's impersonal scheme of things but matters of social decision made for reasons of public polity and administrative convenience. They are legislated quantities.

The historical researches of Louis Couturat saved the logical work of Leibniz from the oblivion of neglect and forgetfulness. They revealed that Leibniz developed in succession several versions of a “logical calculus” (calculus ratiocinatororcalculus universalis). In consequence of Couturat's investigations it has become well known that Leibniz's development of these logical calculi adumbrated the notion of a logistic system; and for these foreshadowings of the logistic treatment of formal logic Leibniz is rightly regarded as the father of symbolic logic.It is clear from what has been said that it is scarcely possible to overestimate the debt which the contemporary student of Leibniz's logic owes to Couturat. This gratitude must, however, be accompanied by the realization that Couturat's own theory of logic is gravely defective. Couturat was persuaded that the extensional point of view in logic is the only one which is correct, an opinion now quite antiquated, and shared by no one. This prejudice of Couturat's marred his exposition of Leibniz's logic. It led him to battle with windmills: he viewed the logic of Leibniz as rife with shortcomings stemming from an intensional approach.The task of this paper is a re-examination of Leibniz's logic. It will consider without prejudgment how Leibniz conceived of the major formal systems he developed aslogicalcalculi – that is, these systems will be studied with a view to the interpretation or interpretations which Leibniz himself intends for them. The aim is to undo some of the damage which Couturat's preconception has done to the just understanding of Leibniz's logic and to the proper evaluation of his contribution.