Spinoza: Philosophical Method

This chapter argues that the standard conception of Spinoza as a fellow-travelling mechanical philosopher and proto-scientific naturalist is misleading. It argues, first, that Spinoza’s account of the proper method for the study of nature presented in the Theological-Political Treatise (TTP) points away from the one commonly associated with the mechanical philosophy. Moreover, throughout his works Spinoza’s views on the very possibility of knowledge of nature are decidedly sceptical (as specified below). Third, in the seventeenth-century debates over proper methods in the (...) sciences, Spinoza sided with those that criticized the aspirations of those (the physico-mathematicians, Galileo, Huygens, Wallis, Wren, etc) who thought the application of mathematics to nature was the way to make progress. In particular, he offers grounds for doubting their confidence in the significance of measurement as well as their piece-meal methodology (see section 2). Along the way, this chapter offers a new interpretation of common notions in the context of treating Spinoza’s account of motion (see section 3). (shrink)

In this paper, I argue for a novel reading of Spinoza’s position in his exchangewith Boyle about Boyle’s experiment with nitre. Boyle claimed to have shownthrough experiments that nitre ceased to be nitre after heating. Spinozadisagreed and proposed the alternative hypothesis that nitre has changed itsstate and not its nature. Spinoza’s position was construed in the literature asrational scepticism denying that experiments can yield knowledge ofessences because all sensory experience is underdetermined and open tomultiple interpretations. I argue for an alternative (...) reading of Spinoza’sposition which focuses on Bacon’s notion of crucial instance. According tothis reading, Spinoza did not deny the possibility of knowing byexperimentation whether nitre has changed its nature, he asked for a crucialinstance, i.e. an experiment that would refute the hypothesis that nitre haschanged merely its state. Spinoza’s argumentative strategy shows that,contrary to the mainstream reading, the representational content of sensoryideas can be determined even if it does not represent the essence of theobject: we can know with absolute, rather than merely moral, certaintywhether nitre ceased to be nitre without knowing what nitre is. (shrink)

Like most, if not all, of his contemporaries, Spinoza never developed a full-fledged philosophy of mathematics. Still, his numerous remarks about mathematics attest not only to his deep interest in the subject (a point which is also confirmed by the significant presence of mathematical books in his library), but also to his quite elaborate and perhaps unique understanding of the nature of mathematics. At the very center of his thought about mathematics stands a paradox (or, at least, an apparent paradox): (...) mathematics provides Spinoza with an epistemic model. Mathematical knowledge is certain (II/138/9 and II/138/9), clear (IV/261/8), and free from teleological thinking (II/79/33), but the objects of mathematical knowledge – i.e., mathematical entities – are nothing but “auxila imaginationis [aids of the imagination],” (IV/57/16 and II/83/15), entities that are not real and merely assist the imagination in carving the world in manner that is suitable to our limited and distortive cognitive capacities. (shrink)

Spinoza reasons about impossibilities on a regular basis. But he also says they're unthinkable and that reasoning is a mental process. How can he do this? The paper defends a linguistic account of counterpossible inferences in Spinoza's geometrical method.

Spinoza's Ethics self-consciously follows the example of Euclid and other geometers in its use of axioms and definitions as the basis for derivations of hundreds of propositions of philosophical si...

This paper offers a new interpretation of the young Spinoza’s method of distinguishing the true ideas from the false, which shows that his answer to the sceptic is not a failure. This method combines analysis and synthesis as follows: if we can say of the object of an idea which simple things underlie it, how it can be constructed out of simple elements, and what properties it has after it has been produced, doubt concerning the object simply makes no sense. (...) The paper also suggests a way in which this methodology connects to the ontology of the Ethics. (shrink)

This paper examines Spinoza’s view on the consistency of mental representation. First, I argue that he departs from Scholastic tradition by arguing that all mental states—whether desires, intentions, beliefs, perceptions, entertainings, etc.—must be logically consistent. Second, I argue that his endorsement of this view is motivated by key Spinozistic doctrines, most importantly the doctrine that all acts of thought represent what could follow from God’s nature. Finally, I argue that Spinoza’s view that all mental representation is consistent pushes him to (...) a linguistic account of contradiction. (shrink)

This chapter will discuss Spinoza’s critique of free will, though our brief study of this topic in the first part of the chapter will aim primarily at preparing us to address the main topic of the chapter, which is Spinoza’s explanation of the reasons which force us to believe in free will. At times, Spinoza seems to come very close to asserting the paradoxical claim that we are not free to avoid belief in free will. In the second part of (...) the chapter I will closely examine Spinoza’s etiological explanation of how we come to form the belief in free will. In the third part, I will raise and respond to a crucial objection to Spinoza’s explanation of the formation of our belief in free will. I will then turn to examine Fichte’s intriguing claim that Spinoza’s position on the issue of free will suffers from an internal contradiction, as evinced in Fichte’s suggestive remark: “Spinoza could not have been convinced of his own philosophy. He could only have thought of it; he could not have believed it [Er konnte seine Philosphie nur denken, nicht sie glauben].”. (shrink)

Adequate and inadequate ideas play a central role in Spinoza’s system. A number of recent commentators have suggested that the internality or externality of an idea’s immediate cause is a necessary and sufficient condition of the idea’s adequacy or inadequacy, respectively. I show that this thesis is subject to counterexample and briefly explore the significance of this critique for recent interpretations. I offer an alternative interpretation on which adequate and inadequate ideas are characterized by the manner in which they grasp (...) their objects. Adequate ideas conceive of their objects as following from God. Inadequate ideas conceive of their objects as affecting the body at a time and place. (shrink)

Spinoza ’s letter of June 2, 1674 to his friend Jarig Jelles addresses several distinct and important issues in Spinoza ’s philosophy. It explains briefly the core of Spinoza ’s disagreement with Hobbes’ political theory, develops his innovative understanding of numbers, and elaborates on Spinoza ’s refusal to describe God as one or single. Then, toward the end of the letter, Spinoza writes: With regard to the statement that figure is a negation and not anything positive, it is obvious that (...) matter in its totality, considered without limitation [indefinitè consideratam], can have no figure, and that figure applies only to finite and determinate bodies. For he who says that he apprehends a figure, thereby means to indicate simply this, that he apprehends a determinate thing and the manner of its determination. This determination therefore does not pertain to the thing in regard to its being [esse]; on the contrary, it is its non-being [non-esse]. So since figure is nothing but determination, and determination is negation [Quia ergo figura non aliud, quam determinatio, et determinatio negatio est], figure can be nothing other than negation, as has been said. Arguably, what is most notable about this letter is the fate of a single subordinate clause which appears in the last sentence of this passage: et determinatio negatio est. That clause was to be adopted by Hegel and transformed into the slogan of his own dialectical method: Omnis determinatio est negatio. Of further significance is the fact that, while Hegel does credit Spinoza with the discovery of this most fundamental insight, he believes Spinoza failed to appreciate the importance of his discovery. The issue of negation and the possibility of self-negation stand at the very center of the philosophical dialogue between the systems of Spinoza and Hegel, and in this paper I will attempt to provide a preliminary explication of this foundational debate between the two systems. In the first part of the paper I will argue that the “determination is negation” formula has been understood in at least three distinct senses among the German Idealists, and as a result many of the participants in the discussion of this formula were actually talking past each other. The clarification of the three distinct senses of the formula will lead, in the second part of the paper, to a more precise evaluation of the fundamental debate between Spinoza and Hegel regarding the possibility of self-negation. In this part I will evaluate the validity of each interpretation of the determination formula, and motivate the positions of the various participants in the debate. (shrink)

The history of western philosophy is split to its core by a long-standing, fundamental dispute. On the one hand there are the so-called empiricists, like Locke, Berkeley, Hume, Mill, Russell, the logical positivists, A. J. Ayer, Karl Popper and most scientists, who hold empirical considerations alone can be appealed to in justifying, or providing a rationale for, claims to factual knowledge, there being no such thing as a priori knowledge – items of factual knowledge that are accepted on grounds other (...) than the empirical. And on the other hand there are the so-called rationalists, like Descartes, Spinoza, Leibniz, Bradley, McTaggart, who hold that a priori knowledge does exist, and even plays a crucial role in science. This long-standing dispute is resolved by the line of thought developed in this essay. The empiricists were right to deny the existence of a priori knowledge where this means factual knowledge of apodictic certainty justified independently of any appeal to experience. They were wrong, however, to deny the existence of a priori knowledge where this means conjectural items of factual knowledge whose acceptance is justified independently of any appeal to experience. Science requires there to be a priori knowledge in this latter sense, and two items of such knowledge will be exhibited. In addition to resolving this empiricist/rationalist dispute, the essay also develops a new conception of science – aim-oriented empiricism – and solves the long-standing problem of what it means to say of a theory that it is unified or explanatory. Furthermore, aim-oriented empiricism does not just change our conception of science; it requires that science itself needs to change. Science needs to become much more like the 17th century conception of natural philosophy, intermingling consideration of testable theories with consideration of untestable metaphysical, epistemological and methodological ideas. The whole relationship between science and the philosophy of science is transformed. The philosophy of science, construed as the exploration and critical assessment of rival ideas about what the aims and methods of science ought to be, ceases to be a meta-discipline, and becomes an integral part of science – or natural philosophy – itself. (shrink)

In this paper I argue for a priori conjectural scientific knowledge about the world. Physics persistently only accepts unified theories, even though endlessly many empirically more successful disunified rivals are always available. This persistent preference for unified theories, against empirical considerations, means that physics makes a substantial, persistent metaphysical assumption, to the effect that the universe has a (more or less) unified dynamic structure. In order to clarify what this assumption amounts to, I solve the problem of what it means (...) to say of a theory that it is unified. There are, I argue, eight different kinds of unity important in theoretical physics, all varieties of one basic idea. This provides us with a precise way of partially ordering physical theories with respect to their degree of unity. It also leads to a hierarchical view of physics, according to which physics makes a number of increasingly insubstantial metaphysical assumptions concerning the comprehensibility and knowability of the universe. Two of these are identified as constituting a priori conjectures. I conclude by arguing that the view developed in the paper resolves the traditional clash between empiricism and rationalism in the philosophy of science, and has important implications for science, and for academic inquiry more generally. (shrink)

Spinoza scholars have claimed that we are faced with a dilemma: either Spinoza's definitions in his Ethics are real, in spite of indications to the contrary, or the definitions are nominal and the propositions derived from them are false. I argue that Spinoza did not recognize the distinction between real and nominal definitions. Rather, Spinoza classified definitions according to whether they require a priori or a posteriori justification, which is a classification distinct from either the real/nominal or the intensional/extensional classification. (...) I argue that Spinoza uses both a priori and a posteriori definitions in the Ethics and that recognizing both types of definitions allows us to understand Spinoza's geometric method in a new way. We can now understand the geometric method as two methods, one resulting in propositions that Spinoza considers to be absolutely certain and another resulting in propositions that Spinoza does not consider certain. The latter method makes use of a posteriori definitions and postulates, whereas the former method uses only a priori definitions and axioms. (shrink)

This article examines the seventeenth-century debate between the Dutch philosopher Benedict de Spinoza and the British scientist Robert Boyle, with a view to explicating what the twentieth-century French philosopher Gilles Deleuze considers to be the difference between science and philosophy. The two main themes that are usually drawn from the correspondence of Boyle and Spinoza, and used to polarize the exchange, are the different views on scientific methodology and on the nature of matter that are attributed to each correspondent. Commentators (...) have tended to focus on one or the other of these themes in order to champion either Boyle or Spinoza in their assessment of the exchange. This paper draws upon the resources made available by Gilles Deleuze and Felix Guattari in their major work What is Philosophy?, in order to offer a more balanced account of the exchange, which in its turn contributes to our understanding of Deleuze and Guattari’s conception of the difference between science and philosophy. (shrink)