Main Philosophical Directions

Directions of Epistemological Theory

Ontologism

While ancient philosophy, in its empirical pursuits, did not transcend the boundaries of naïve empiricism, it also remained confined within the corresponding level of naïve empiricism in its rationalist direction, namely, apriorism. Nonetheless, the philosophical creation in which rationalist thought finds its first complete expression—the dialectic of Plato—already contains the seeds for further development. The premise that dialectical thought leads to concepts representing the essence of things inherently implies another: that, conversely, one can prove existence through these concepts. Indeed, Plato’s "Phaedo," alongside various arguments in favor of the immortality of the soul that retain significance in philosophy, also presents a purely ontological proof. This proof asserts that since the soul is the principle of life, it inherently excludes its opposite—death. However, this application of the dialectical method is so isolated within the system that it could not influence the formation of the doctrine of ideas or its further development. The advancement to a higher level of rationalism in philosophy was prompted by two phenomena in philosophical thought that emerged at different times: the theological speculation of the scholastics in the eleventh century and the mathematical inquiries of the early modern period. Earlier scholasticism consciously replaced the apriorism of ancient philosophy with ontologism, which dominates the dogmatic systems of more recent philosophy; while in the seventeenth century, under the influence of mathematical studies, this second fundamental form of rationalism achieved its final, rigorous shape.

The significant role that the philosophy of the early scholastic period played in the further development of rationalism, a role prepared especially by Augustine among the Church Fathers, corresponded entirely to the task facing scholastic philosophy. The problem of ancient philosophy consisted of fully explaining the world; the concept of God found its place only in relation to this task. Thus, even the most universal concepts could never be entirely detached from the empirical foundations provided by the sensory world. Therefore, where there was a tendency to resolve the problem of the world, even according to the demands of reason, the only path to achieving this goal remained that of apriorism, which contained empirical elements. The speculative thought of Christian medievalism, from the very beginning, was in a completely different position. It showed comparatively little interest in cosmological problems, being more attracted to the supersensory realm. Hence, when the need arose to understand the dogmas of faith according to the principle of "credo ut intelligam," it must have been apparent, due to the complete transcendence of the objects of faith, that in knowing these kinds of objects, reason must rely entirely upon itself: any attempt in this area to ascend from the world of experience to the supersensory world would, strictly speaking, undermine the purity and exaltation of the latter. A clear testament to this line of thought can be found in the method established by Anselm of Canterbury, who first formulated the ontological proof of the existence of God. Initially, he attempted, like Augustine, to derive the necessity of assuming absolute goodness from the concept of relative goodness. Against this mode of proof, he later developed doubts, considering that in this case, the absolute would become dependent on the relative, and knowledge of God would hinge upon knowledge of finite things. He thus sought to replace it with another approach: he aimed to prove the existence of the absolute from its own absolute nature. Accordingly, his ontological proof of the existence of God directly arises from the definition of God as “the greatest being.” Even an atheist, in Anselm's view, must acknowledge that such an absolutely greatest being is not only possible but necessarily thinkable. However, this concept of the absolutely greatest being is not merely a thought; it must correspond to external reality. If the absolutely greatest being existed only in thought, then one could conceive of something greater than it, since adding the notion of reality to the thought of the greatest being would yield the idea of a being greater than that which exists only in thought. Thus, the thinkable absolutely greatest being must also exist in reality; mere thought cannot constitute the absolutely greatest being. In later formulations, this proof is often shortened: existence is directly considered a necessary attribute of the most perfect being, while non-existence is seen as an objective sign of imperfection. Through this abbreviation, the close relationship between ontologism and its predecessor, apriorism, regarding the form of its proof, is lost: in the earlier proof, the thinkability of the concept was taken as given, and reality corresponding to the thinkable concept was recognized as a necessary correlate of the concept. However, in this earlier mode of proof, a clear connection, as well as a significant difference, between ontologism and apriorism is revealed. While apriorism directly attributes external reality to all ideas in thought—for instance, in Plato's doctrine of ideas, each concept objectively corresponds to an idea—ontologism establishes specific criteria by which one can discern whether a corresponding reality pertains to a given concept. Since these criteria must reside solely in the thinking of concepts, they evidently reduce to the requirement that both the concept itself and the reality corresponding to it be thought of as necessary. This requirement, naturally, could and should have initially arisen regarding the objects of faith due to their transcendent nature: they could not be found in experience but only in thought, and therefore could only be justified through thought.

The exclusively theological direction of the speculative thought of this early scholastic period also contributed to the shortcomings inherent in the ontological trend of the time. Later, it did not coalesce into a coherent system of knowledge; rather, it appeared in a series of discrete, isolated propositions that were, in essence, not free from empirical elements and possessed, more in appearance than in substance, the necessary character for thought. This observation applies, for example, to Anselm's ontological proofs concerning the dogmas of the Trinity and redemption. In such a forced application of the ontological method, one could observe a foundational reason why later scholasticism abandoned ontologism and returned to a half-aprioristic, half-empirical direction; on the other hand, this was also encouraged by Aristotle’s philosophy, which held a leading position during this time.

The revival and subsequent development of the ontological direction belong to the dawn of modern philosophy. Due to the influence of mathematical reasoning on the evolution of this new philosophy, the ontological direction acquires a distinctive character. In Descartes' philosophy, this character is somewhat overshadowed by other elements of his system, which are akin to ancient Christian speculation. By prioritizing the self-evidence of the thinking "I" alongside Augustine, Descartes naturally adheres to a psychological method of inquiry in his ontological proof of God's existence. This method posits the self-consciousness of the thinking subject as the foundational point for all other a priori knowledge inherent in our spirit. Descartes transforms Anselm's logical proof into a psychological one: in demonstrating God's existence, he focuses not on reality as a positive definition necessarily appended to the concept of the absolute, but rather on the fact that the subjective notion of the absolute in our consciousness cannot be merely a product of individual self-awareness. Therefore, it points to the immediate action of God upon our soul. Because of this characteristic, Descartes' ontological proof of God's existence approaches Plato's view on the existence of ideas within sensory objects and his doctrine of reminiscence. Indeed, Descartes' teaching on innate ideas reflects a return to Platonic apriorism. However, by limiting the realm of concepts, initially inherent to humans and shaped by super-sensory archetypes—self-consciousness, mathematical axioms, and the idea of God—Descartes does not unite everything, as Plato's theory of ideas sought to encompass all conceivable knowledge, both a priori and empirical. Instead, he divides the entire domain of the knowable into two parts, one of which, drawing from innate ideas, requires no assistance from experience, while the other solely represents empirical knowledge. Consequently, although rational knowledge is freed from the empirical impurities present in ancient apriorism under Descartes' influence, he feels compelled to cater to the claims of positive sciences, recognizing experience as a source of knowledge, albeit a less valuable and yet fully independent one. Thus, this initial attempt to apply ontologism to secular philosophical problems, alongside a return to previous levels of apriorism, inevitably results in significant concessions to empiricism.

Conversely, this transfer of ontologism to a new domain contributed significantly to its progress, allowing this direction to acquire its philosophical significance. As mathematical truths possess a unique certainty—its geometric clarity is presented in immediate contemplation—mathematical obviousness becomes a model of the inner necessity required by the ontological direction. This gives rise to a new concept, the notion of intuitive knowledge, which in theological ontologism had yet to be sufficiently distinguished from the concept of demonstrative knowledge. In the ontological proof of the concept of God and in other dogmatic proofs constructed in its likeness, the proven positions arise from logical demonstration, where the premises, being merely simple verbal definitions—such as definitions of the absolutely highest being—lack inherent certainty and derive it again through logical proof. In contrast, mathematical axioms are striking in their complete obviousness, even though they cannot, in a strict sense, be proven. Therefore, Descartes, keeping the self-evidence of mathematical axioms in view, asserted that ultimately every true knowledge must rest upon principles that cannot themselves be proven but are clear and obvious in themselves. Thus, a general concept of intuitive knowledge emerged, specifically distinguished from demonstrative knowledge and presupposed by the latter. Key instances of such intuitive knowledge, beyond mathematical axioms, are found in the proposition "cogito, ergo sum" as well as in the existence of God. The latter compelled him to transform the ontological proof of God's existence into a psychological one; it is only through this transformation that the idea of God shifts from a result obtained through inference into immediate internal contemplation. The self-evidence of thought, mathematical axioms, and the idea of God now become equally intuitive truths—truths that cannot be proven in the strict sense of the word but are self-evident.

Thus, due to the influence of mathematics on the theological ontologism of Christian speculation, a new and immensely significant type of concept emerged for the ontological direction, a concept whose validity lies within the concept itself. It is sufficient merely to define this concept clearly to understand its object as necessary. Such a concept may constitute the content of intuitive knowledge, yet it does not embody demonstrative knowledge. It is distinguished from the latter, which is merely indirect, by its immediate clarity; in this clarity lies the foundation that it cannot be deduced from anything else, whereas further propositions may be derived from it through proof. This situation indeed reflects the case with mathematical axioms, which serve as typical examples of intuitive knowledge. The influence of mathematics on the ontological direction was also manifested in the fact that, from this time forward, as long as this form of rationalism remained the dominant direction, the Euclidean method of proof was primarily employed in philosophy and the sciences influenced by it. Truths recognized intuitively were assumed as definitions and axioms and then further propositions were logically derived from them.

However, the diversity of the initial concepts posited by Descartes, which substantiated the crucial notion of intuitive knowledge, precluded the use of a single demonstrative method and thus facilitated the incorporation of empirical elements into the system. By retaining only one of the three Cartesian intuitive ideas—the idea of God—and expanding it, in accordance with its comprehensive application, to the idea of substance while also including within substance the objects of mathematical knowledge, extended things, and self-knowledge of thinking beings, Spinoza could strictly follow the ontological direction based on the foundations established by Descartes. He defines the concept of substance as intuitively certain: "Per substantiam intelligo id quod in se est et per se concipitur." From this definition, it naturally follows that the concept of substance cannot be deduced from any other concept, and therefore, substance cannot be thought of as dependent on anything else. Thus, from the definition of substance, not only the intuitive certainty of substance emerges, but also the realization that substance is the sole object of intuitive knowledge and, therefore, the only object of knowledge in the strictest sense, as there is no other rational knowledge aside from knowledge of intuitively certain content and that derived from it through logical conclusions. Thus, substance is not only a concept grounded in itself and necessarily encompassing its subject, but it is also the only concept containing all that previously constituted an independent subject of intuitive certainty. The concept of substance is synonymous with the concepts of God and nature; nature represents a composite of extended and thinking things, "res extensa" and "res cogitans." Since in this case the notion of intuitive certainty coincides with the notion of the unconditional, it naturally follows that the fundamental ontological concept leads to the idea of the absolutely infinite, which, excluding all limitations, can only be understood from itself and exist solely through itself. "Causa sui" represents a condensed expression that encompasses all the aforementioned definitions inherent to substance; it indicates, on one hand, the absolute independence of the infinite substance and, on the other hand, the necessity inherent in the thought and existence of substance, which is imparted to all that depends upon it, and thus to each individual thing. The strict determinism prevailing in Spinoza's system—the determinism whereby alongside substance, every attribute and mode succumbs to inevitable necessity—follows directly from the necessity of both the concept and its object being thought as necessary.

Thus, Spinoza's system represents a rigorous embodiment of ontologism. Due to the unity of substance, the requirement of necessity for being and thinking, as outlined in the most fundamental ontological concept, is not only perfectly fulfilled, but because of the all-encompassing nature of this concept, it is also fulfilled in relation to all particulars: the ontological foundation is not limited to the already established sum of specific truths, but excludes, strictly speaking, any other mode of knowledge, much like a singular causa excludes all other autonomous causes. However, therein lies an insurmountable flaw in Spinoza's system. Since everything particular is reduced to substance, its attributes, and modes, the knowledge of this singular concept and its abstract characteristics exhausts all that is possible for Spinoza's understanding. Therefore, it becomes impossible for him to transition from the realm of transcendent ideas to empirical reality. Just as a strict explanation of nature based on this doctrine of substance is impossible, so too is the analysis of cognitive functions. Each separate act of cognition, while it remains within the finite, appears as a deceptive phantom, disappearing the moment the particular is viewed in its conditionality through the unconditional, from the perspective of eternity "sub specie aeternitatis"—a perspective where, again, there can be no genuine understanding of the particular, for in this case, the finite entirely vanishes within the infinite. Thus, it is inevitably necessary to introduce, for the sake of this particular, the concept of imperfect, inadequate knowledge: knowledge which, strictly speaking, is not knowledge at all and which is an unavoidable consequence of the limitations of human nature. Consequently, the realm of knowledge splits into two domains: that of true knowledge, which, strictly speaking, contains only the abstract concept of substance and nothing else, and that of merely illusory inadequate knowledge, which, possessing all the richness of experience, is entirely outside the realm of genuine understanding.

If Spinoza, in his strict adherence to ontologism, arrived at a complete rupture with empirical knowledge—though he could not but acknowledge its existence in the ordinary form prevailing in practical life, immediately alongside pure understanding in concepts—Leibniz, in this regard, took a viewpoint reconciling the claims of pure thought with the demands of experience. He too is an advocate of ontologism. However, for him, the latter is moderated and brought into closer connection with experience through two key elements: firstly, through the starting point of his system, which is nothing other than the content of experience in its entirety; and secondly, through the fundamental concept of his system. On one hand, Leibniz presupposes the given world of phenomena in its diversity and juxtaposes it with the simple, which is necessarily required by the complex. Thus, he arrives at his concept of absolutely simple substance. This concept is also derived ontologically: based on the premise that it is conceived as necessary, the existence of objects corresponding to it, namely simple substances or monads, is proven. However, for Leibniz, the necessity of the conceivability of this concept is itself proven by the existence of the complex, and since the latter is given only empirically, in this case, the ontological proof does not stem from the obviousness of the concept itself; rather, it derives the obviousness of this concept from the notion that is actually given in experience. Therefore, the aforementioned fundamental concept of Leibniz's system is not self-evident, nor is it intuitively self-evident; instead, it gains validity through proof, a proof that originates from experience. Thus, Leibniz returns to the ancient-scholastic imperfect, demonstrative use of the ontological method, a use that often required recourse to empirical presuppositions. This directly links to another aspect in which Leibniz's ontologism intersects with empiricism. By defining substance as an absolutely simple entity and establishing an infinite multitude of simple substances to understand the diversity of the world of phenomena, Leibniz had to position them in relation to one another. The foundation for this, as in Descartes and Spinoza, is provided by mathematics, and in this sense, his system is thoroughly infused with the spirit of modern ontologism, which employs mathematical principles. However, the principle of continuity, drawn from the method of infinitesimals he discovered, does not provide, in contrast to the principle of intuitive certainty found in Descartes and Spinoza, an internal necessity that, when transferred to substance, becomes absolutely coercive. On the contrary, as with the investigations of continuities in differential calculus, applying this mathematical principle to the philosophical concept of substance leads to the principle of purposiveness. Thus, in Leibniz's view, the dominant concept is not that of an absolute cause with its internal necessity, which excludes any teleological consideration, but rather that of purpose, characterized by its inherent freedom, which arises from the indeterminate relationship between means and ends. At the same time, in this principle, which offers ample scope for fantastical constructions, Leibniz returns to Aristotle's apriorism. Consequently, the advantage of Leibniz's system from both aesthetic and intellectual perspectives emerges—an advantage manifest in the establishment of the ideas of development and universal harmony and in adaptation to scientific and psychological experience. However, alongside these advantages, there exists an imprecise application of the ontological method that leaves a great deal to arbitrariness.

It is noteworthy that, despite the empirical character of Leibniz's system regarding its starting point and goals, it too, owing to the still prevailing ontologism within it, failed to achieve an actual reconciliation of the world of concepts obtained through speculative means with the empirical world. Any empirical knowledge, according to Leibniz, is a "vague representation." Although this expression, due to its affirmative character, stands in contrast to the merely negative characterization of empirical knowledge provided by Spinoza as "imperfect," indicating a tendency to concede at least a relative right to experience, even here, experience is fundamentally recognized as a less valuable mode of knowledge compared to rational understanding. Between empirical knowledge and reliable a priori rational understanding lies a chasm that is not bridged by the acknowledgment that the empirically given world of phenomena is conditioned by the metaphysical essence of things. For here, the relationships between the world of phenomena and being are not at all indicated; even through the establishment of specifically different laws for both domains—logical axioms of identity and contradiction for the rational domain, and the principle of "sufficient reason" for the empirical domain—such relationships are simply deemed impossible.

In the subsequent rationalism of the eighteenth century, the ontological direction dominates in both its forms, as it has manifested in the two systems of modernity we have just examined: the causal and the teleological forms. However, within this, the teleological direction generally prevails, not only in philosophy but also in the individual sciences, particularly in natural sciences. Even mechanics prefers a teleological formulation of its general principles, and in organic natural sciences, teleological explanation is often considered the only viable approach. In this context, the clear distinction between causal and teleological understandings becomes lost: both, especially in the exact sciences, completely coincide and are regarded as entirely equivalent. In the philosophy of this time, primarily in Wolff's philosophy, and in the individual sciences influenced by it, moreover, under the influence of sober, rationalistic common sense, the notion of purpose transforms into that of utility, specifically in relation to humanity as the central aim. Thus, anthropopathic teleology arises, which, while still retaining the external foundations of ontologism, regards the facts of experience as firmly established foundations from which it proceeds in teleological explanations. Only for ideas inaccessible to experience, such as God and immortality, does the scholastic ontological method of proof come to aid. Therefore, the discord between thought and experience that was evident in previous systems of ontologism vanishes; here, it evolves into an unprincipled dogmatic system that must inevitably succumb to the blows of criticism directed at its foundational presuppositions. Indeed, this final scion of ontologism fell under the onslaught of Kantian criticism. Rationalism, meanwhile, had not yet exited the stage. It emerged in its third form based on critical philosophy: in panlogism.