Nature and Norm in Medieval and Early Modern Conceptions of Modality and Agency

An investigation into the philosophical background and conceptual foundations of modern notions of necessity, possibility, autonomy and rational action

Project supported by the Swedish Research Council (Vetenskapsrådet) 2006-2007.

  • Professor Lilli Alanen, Department of Philosophy, Uppsala University
  • Tomas Ekenberg, Department of Philosophy, Uppsala University


This project examines influential views of agency and the conditions of voluntary and rational action in the light of the philosophical conceptions of modality with which they are connected. It explores some developments in philosophical theories of modality that have not been investigated, and analyzes how their different ways of conceiving necessity and possibility affect the accounts given of agency and of the roles of will and reason in human action. It focuses on the relation between naturalist models of action explanation and norm-centred accounts of free agency and the problems that the tensions between these two approaches generate. Supposedly, Aristotle's brand of teleological and normative naturalism (henceforth "Aristotelian naturalism") has little room for such tensions, but tensions do appear in neo-Platonist and especially in Platonist Christian thought, where human nature after the fall falls short of conforming to the divine standard of Goodness and Rightness. Tensions between naturalistic and normative approaches take different forms depending on how "nature" and physical science is understood in different contexts during the medieval and early modern period, and also on what the source of norms is taken to be: Nature itself, a transcendent Deity or Society. The mechanistic model of explaining nature propagated by Descartes in the early modern period, a "mechanistic naturalism", excluded norms and goals from physical nature but they were still presupposed as operative through either divine or human agency. The tensions that this split between what Wilfrid Sellars called "the logical space of causes" and "the logical space of reasons" are reflected also in contemporary discussions of agency — notably in debates about intentions and action explanations in terms of causes vs. reasons, or about the possibility, more generally, of a science of rationality and its status in relation to present-day "Scientific naturalism" with its physicalist interpretations of nature (see, e.g., Davidson, 1995). It is our contention that some of these tensions can be solved or at least brought into focus and clarified by a better understanding of the philosophical background and roots of conflicting views and of the modal conceptions presupposed in these discussions.

Agency and Modality: The Ancient and Medieval Background

What defines the agent, or self?

I. The power of reason   Since ancient times philosophical discussions of voluntary agency and the role of rational deliberation and choice for human action and responsibility have been conducted in terms imported from juridical or legislative contexts. Indeed in Plato's now most widely read dialogue, The Apology, Socrates rehearses the reasons for his actions and way of life in front of his judges in a public trial. Socrates could conceivably have acted differently but what he did (e.g. challenging or provoking the Athenians) he did deliberately, by voluntary choice. Aristotle, who formulated a classic version of what in contemporary debates is called the "belief-desire model" of action, argued that we always desire the good, that our desire naturally conforms to what our intellect presents as the good, and that action follows automatically when the process of deliberating about the suitable means of attaining the desired good has come to an end. Reason ideally operates like the enlightened judge who, having scrutinized the evidence of the case and the available means, passes her verdict on the optimal course of action in the given circumstance. This deliberating and choosing is something that the agent is thought to be doing independently of external forces, and reaching the decision is seen as a paradigm case of an action that is "up to us", or "in our power" (gr. eph'emin). This picture carries with it a strong commitment to the rationality of human agents. It does not imply that we in fact always act rationally, but that in so far as we have reason we can do so. For the capacity for rational deliberation and action is what is characteristic of human agents and sets them apart from animals and young children, who may act voluntarily — i.e., as they please — in the absence of external coercion or obstacle, but who do not act rationally and are not considered morally accountable for their doings. (See Aristotle, Nichomachean Ethics III) What, in modal terms, does the rational capacity here invoked commit us to? Aristotle's discussion of the sea-battle (in De interpretatione IX) raised questions about the role and usefulness of deliberation if the future is determined in advance which provoked an enormous amount of discussion from late antiquity onwards. The project studies repercussions of these debates during the medieval and early modern period, focusing on questions concerning the role and power of reason in determining our actions. It analyses the modal terms used in these discussions and the conceptions of modality that they are embedded in or presuppose.

II. The power of will   The discussion of the conditions of rationality and moral agency in the broadly Aristotelian philosophical framework of the high middle ages centred on the relation between will and reason, and their respective roles in free choice and agency. Action is free or voluntary when it is "up to us" — when it depends on the agent herself. But under what circumstances do actions express the true self or nature of the agent; when are they truly his own? While ancient and medieval followers of Plato and Aristotle typically answered this question by appealing to reason and rational capacities, some thinkers, inspired by the teachings of Augustine, instead emphasized the will or the desire of the governing part of the soul (i.e., reason) as the defining mark of a person. In the context of Aristotelian naturalism these two views need not be in conflict. Reason is the highest human capacity and comes with norms and desires of its own, and it is her natural (and rational) desire for the Good and the True that defines the human being. When a person knows the true and the good, she naturally desires it. Persons who do not conform to what reason dictates must on this view have been overcome by "alien" forces, e.g., by the desires and passions of the lower parts of the soul, or by external compulsion. The phenomenon of being weak-willed (doing the worse while seeing the better) was often explained in this "intellectualist" tradition by some failure or other in the use of the cognitive power. This picture of agency was questioned by Christian "voluntarists" in the late thirteenth century who, like Augustine, saw the human will or desire as the source of evil and who, while agreeing with the basics of Aristotelian psychology and philosophy of action, took it to be important to show that human agents can sin voluntarily, out of a free decision (liberum arbitrium) and of their own will. Here will is seen as an active cause (a self-mover) operating independently of reason or intellect in the causation of actions. (See e.g. Kent, 1995, and Normore, 1998.) Full knowledge of the good pursued is not, on this view, a sufficient condition for right action. Right action requires in addition an independent disposition of the will. The nature of this power of will and its mode of operation are regretfully not very clear. Few theories, moreover, are easily classified as purely "voluntarist" or "intellectualist". This project contributes to recent research on these issues by examining accounts of the conditions of agency which do not conform to these two models. The result of the investigation of the medieval theories will be used in comparative analysis of some influential early modern views of modality and agency.

Specific Research Goals

The project is divided in two closely interrelated parts, where the main focus of the first (part A) is on discussions of modality from the medieval to the early modern period, while the second (part B) investigates the rethinking of the conditions of agency in the framework of early modern mechanistic science of nature.

PART A: Necessity, Power and Agency In Medieval and Early Modern Philosophy

The case of Anselm of Canterbury (1033-1109), whose views are the starting point here, may serve to illustrate the difficulty mentioned above. It is an open question as to how his views of moral agency and the powers it presupposes should be properly understood, for they do not conform to any of the models appealed to in recent research. Anselm influenced many thinkers, notably Duns Scotus (1265/6-1308), who adopts the Anselmian distinction between two "wills" or inclinations, the will or desire for the useful and the desire for the good in itself or justice. The first operates as a natural capacity striving for perfection, where the goal is what is beneficial and contributes to the happiness of the agent herself. The latter is a moral will, seeking the just or the good for the sake of the good in itself. A suggestion that this project wants to explore more fully is to what extent Anselm's "two wills" doctrine can be seen as anticipating Kant's dichotomy between the moral and the natural will. Ekenberg (2005) shows, contrary to what has been recently argued, that Anselm does not locate freedom in the choice between two opposed inclinations; indeed, that freedom in Anselm's sense, although it is a real power of the moral agent, lies not in an ability to do otherwise and hence does not commit Anselm to indeterminism or libertarianism of the kind threatening the "voluntarist" position. To shed more light on these issues a careful investigation of the discussions of Anselm's views among his critics and followers is required. It will be paralleled by an examination of later developments of similar ideas recurring in some early modern theories of modality.

The specific research aims in this part of the project are: (1) to sort out the views of necessity and possibility taken as relevant in the discussions of free agency among Anselm's medieval followers and critics; (2) to examine and critically evaluate later developments of similar ideas in early modern accounts of modality, and, more specifically, to (3) determine if and to what extent the ancient way of understanding modality in terms of real powers of agents instantiated in Anselm's thinking is at work e.g. in Descartes's account of necessity as founded in God's will and power on the one hand, and in Spinoza's view of self-causing nature on the other. A related task is (4) to examine how Spinoza's and Descartes's views of modality are reflected in their accounts of action. How should the modal terms used in their discussions of agency (human, divine/natural agency) be understood and what conceptions of necessity and possibility do they imply? Both are committed to the idea of the necessity of the present, both argue, in very different and partly opposed ways, for the possibility of free human agency. But what kind of freedom are they defending — what kind of action is possible in the framework of their mechanistic conceptions of nature where goals and value have no explanatory force? This part of the project is completed by (5) the analysis of the very different solutions proposed by Leibniz and by Hume respectively to problems raised by Descartes's and Spinoza's treatment of modality and agency.

PART B: Mechanistic Naturalism and Rethinking the Conditions of Agency

The new models of scientific explanation adopted in the early modern period and their application by Descartes and his followers to animal and human behaviour challenged them to rethink the concept of action and the conditions of moral agency, while the emerging ideas of the physical universe as a closed deterministic system posed new problems for intuitions about modality and free choice. The questions raised in the first part of the project are pursued here with special attention to how the traditional notions of reason and will are transformed in the process of mechanization of nature and how these transformations are reflected in the accounts of rational agency, freedom and moral responsibility discussed by 17th and 18th century philosophers.

The medieval philosophical discussions of free agency were concerned with the internal conditions, i.e., the cognitive and conative capacities of the agent and their interrelations. These were spelled out in terms of Thomist faculty psychology based on the Aristotelian tri-partite model of the soul. Descartes and his followers rejected that model and opted for psychological monism more in line with the Stoic conception of the psyche. The soul or mind is identified with reason or the power of thinking generally and considered as one and undivided. It still retains different powers, one of them being reason or intellect, and the other the will, which Descartes in line with his "voluntarist" predecessors took to act independently of reason. The will for Descartes is the faculty by which human beings are the image of their creator, and this free unconditioned will is seen as the highest perfection of man. If Descartes's metaphysical theory of mind as an undivided purely thinking substance is continuous with theories found among his medieval predecessors, his account of the functions of the sentient animal body as part of the mechanical nature breaks with that tradition, and so, consequently, does his view of the mind-body relationship, raising problems that Descartes never manages to solve (Alanen, 2003). As embodied, the human mind is part of nature and subject to its laws, as a purely thinking thing, it is supposed to retain its free will and autonomy. The internal conflicts of parts of the soul are replaced with the opposition between the rational will on the one hand, and the passions caused by the mechanically moved body on the other hand. As is well-known, none of his followers accepted the unstable compromise view of the relation and interaction between mind and body that Decartes proposed. This project is not concerned with that problem per se, but with analyzing different responses among Descartes's sharpest critics to related issues resulting from the conflict between traditional intuitions about modality and agency, and the new picture of nature and natural laws. It also traces the gradual shift of focus from internal (mental or psychic) powers and psycho-somatic conditions to external, juridical and socio-political conditions of agency and morality. It examines how the conceptions of the nature of our cognitive and conative powers are transformed in these discussions.

The specific research topics of Part B are (continuing the numbering of Part A): (6) To examine how the new naturalist accounts of passions offered by Descartes, Hobbes, Spinoza and Hume contribute to reshaping the views of reason and will, reversing the roles of reason — traditionally seen as the governing power — and the passions; (7) to examine the ensuing consequences for the accounts given by Spinoza, Leibniz and Hume respectively of rational agency, focusing on the shift from internal mental capacities to external, physical, social, juridical and political conditions for self-identity and agency; (8) to examine how the relocation of the source of normativity and value from Aristotelian nature, or from God, to human nature, convention or society affects the understanding of agency and moral responsibility. How do the theories here considered solve problems that traditional conceptions of goal-directed autonomous human action posed for the mechanistic and non-teleological models of scientific explanation? Thus Spinoza, who is the first consistently "modern" thinker, in the sense that the idea of a transcendent Deity plays no role at all in his system, excludes norms, goals and values from nature: teleological explanations are but figments of confused human imagination, and there is, supposedly, nothing objectively Good or Bad. Yet he continues to treat activity as superior to passivity and devotes his Ethics to explain how from being passive victims of necessary circumstances and causal laws we are able to ascend to activity and freedom through knowledge and understanding. Is Spinoza developing a wholly new concept of agency or is he merely falling back on Stoic conceptions where acceptance of necessity is seen as the only means of salvation? Is not the ancient notion of a hierarchy of perfection at play in his concept of striving (conatus) which is central to his concept of activity? But then there seems to be a basis in nature for values and ends after all? (9) A closely related issue is that of individuation and self-identity actualized by the rejection by Locke, Spinoza and Hume of a substantial individual soul. What is action without enduring agents? What principle of individuation can/do they appeal to other than the one Spinoza proposes in terms of the ratio of movement and rest that holds the components of the living body together for a while? How do their new principles of association of ideas come into play in the constitution of self-awareness?


Lilli Alanen's works on themes 2-4 (part A) and 6-9 (part B). Tomas Ekenberg concentrates on themes 1-5 (Part A).

The work will result in a series of articles to be published in scholarly journals.

Cited Works

Davidson, Donald (1995). "Laws and Causes", Dialectica 49. Reprinted in Truth, Language and History: Philosophical Essays, Oxford: Clarendon Press, 2005.

Ekenberg, Tomas (2005). Falling Freely: Anselm of Canterbury on the Will, doctoral dissertation, Uppsala University.

Kent, Bonnie (1995). Virtues of the Will: The Transformation of Ethics in the Late Thirteenth Century, Washington, D.C.: The Catholic University of America Press.

Alanen, Lilli (2003). Descartes' Concept of Mind, Cambridge, Mass.: Harvard University Press.

Alanen, Lilli (1991). "Descartes, Conceivability and Logical Modality" in Tamara Horowitz and Gerald Massey (eds.) The Role of Thought Experiments in Science and Philosophy Savage, MA: Rowman & Littlefield Publishers, Inc.

Normore, Calvin G. (1998). "Picking and Choosing; Anselm and Ockham on Choice," Vivarium36:1.

Last modified: 2021-12-07