When thinking about self-knowledge, many people think of a kind of individual knowledge of oneself. Within academic philosophy, for example, self-knowledge is typically about knowing one’s own mental states. How do I know my pains? How do I know my beliefs? Is such knowledge introspective, and what exactly is introspection? Even outside of academic literature people often conceive of self-knowledge as about knowing themselves as individuals in various ways. What kind of character do I have, for example? Or what is my personality type?
Yet historically, many thinkers have taken a different approach to self-knowledge. Thomas Aquinas,Footnote 1 for example, asks: how is it that one comes to know one’s nature? That is, Aquinas is concerned with how one comes to have ‘common’ or ‘universal’ knowledge of one’s soul which is shared in common with other human beings.Footnote 2 More specifically, his treatment of human self-cognition is focused on how we know the intellectual aspect of our nature. Yet if self-knowledge is typically about knowing oneself qua individual, and Aquinas’s account of self-knowledge is about knowing oneself qua human, why call Aquinas’s account of self-knowledge an account of self-knowledge rather than an account of a method for anthropology or something else? After all, one’s nature is not something particular to oneself but something one shares in common with all other human beings. As far as self-knowledge goes, such knowledge would seem to be one of the least individual things one could know about oneself.
This paper sets out to defend knowing one’s nature as a kind of self-knowledge, in particular Aquinas’s account of knowing one’s nature as a kind of self-knowledge. Section 1 begins by distinguishing two features common to contemporary conceptions of self-knowledge, followed by an overview of Aquinas’s account. The question of whether Aquinas’s account is an account of self-knowledge depends on whether it shares in any of the features common to contemporary conceptions of self-knowledge. In Section 2, I distinguish two ways of knowing one’s nature. To demonstrate the distinction, I present a case from literary fiction, Ivan Ilyich from Leo Tolstoy’s The Death of Ivan Ilyich. Ivan provides an example of someone with knowledge of human nature but who lacks self-knowledge of his own nature. In Section 3, I further argue that self-knowledge of one’s nature can be distinguished from the more general knowledge of one’s nature, which I call anthropological knowledge. Section 4 argues that reflection on one’s experience provides first-personal ground that supports self-knowledge of one’s nature. Further, I argue that Aquinas’s account of self-knowledge, insofar as it takes self-awareness as a ground for self-knowledge, is an account of self-knowledge in having first-personal in character.
1. Self-knowledge versus knowing one’s nature
In this section, I distinguish two features common to contemporary conceptions of self-knowledge, give an overview of Aquinas’s account of self-knowledge, and ask whether Aquinas’s conception shares the same features which are common to contemporary conceptions.
When working on a topic, it is sometimes helpful to ask people unfamiliar with the topic for their intuitions. When I have asked such people what they think self-knowledge is about or what comes to mind when they hear ‘self-knowledge’ their answers vary. Some people think of self-knowledge as about knowing their personality. What is my personality type? What kind of character do I have? Or again, some people think of self-knowledge as about knowing what is important to themselves. What are my values? What do I care about most in my life? Others think about self-knowledge as about knowing one’s ‘self’. What is it that makes me ‘me’ at my core? Who am I most essentially?
While these responses vary, common to them all is the idea that self-knowledge is particular. It is not about knowing personality types generally, but about knowing my personality. Likewise, to ask what makes me ‘me’ at my core is not to be concerned with what makes others who they are essentially, but what it is that defines me as an individual. Thus, there is a sense in which self-knowledge is self-knowledge because it is knowledge of oneself which is particular and not knowledge of what applies to others as well.
Particularity is also a prominent feature within discussions of self-knowledge in academic philosophy. As Brie Gertler writes, ‘In philosophy, “self-knowledge” standardly refers to knowledge of one’s own mental states – that is, of what one is feeling or thinking, or what one believes or desires’.Footnote 3 Questions in this literature are focused on how one has knowledge of the particular mental states of oneself rather than questions about the nature of mental states more generally, and one can find others writing on the topic using similar language about knowing one’s own mental states.Footnote 4
Yet particularity is only one feature of self-knowledge. One might have knowledge of oneself that is particular but fails to be known as about oneself. Consider, for example, John Perry’s case of someone who chases a shopper spilling sugar, unaware that they in fact are the shopper spilling sugar.Footnote 5 Such a person might know something particular about herself insofar as she knows that someone (in fact herself) is spilling sugar, but such knowledge is not self-knowledge because she does not know that she is the one spilling sugar. Without knowing that she herself is spilling sugar, her knowledge does not appear to be self-knowledge.
We can describe this aspect of self-knowledge as its first-personal character or its ‘first-personality’ to distinguish it from a knowledge of ourselves in which we are unaware of ourselves as the subject of what we know. We use the first-person pronoun ‘I’ in expressing knowledge of ourselves when we think or say, ‘I am spilling sugar’ rather than third-person nouns such as ‘She is spilling sugar’ or indefinite pronouns such as ‘Someone is spilling sugar’. It is not enough that I know that someone who happens to be me is generous or that someone who happens to be me believes it is raining, but I must know that I myself am generous or that I myself believe it will rain later in order for my knowledge to be self-knowledge. Thus, first-personality is a second feature of contemporary conceptions of self-knowledge in addition to particularity.
That these are the features of self-knowledge presents a conundrum when one turns to certain historical figures, such as Thomas Aquinas, who think of self-knowledge in a less particular way. In fact, the question that Aquinas addresses in his texts on self-knowledge may strike a modern reader as quite odd. In these texts, Aquinas is concerned with the question of whether the intellectual soul or mind knows itself through its essence or through some species.Footnote 6 In order to understand why this is the question Aquinas is concerned with requires understanding the question’s broader context within Aquinas’s account of intellectual cognition and the peculiar place of the human mind between the realms of material and purely intellectual beings. Only after we understand Aquinas’s account better can we ask whether his conception of self-knowledge shares the above features common to contemporary conceptions of self-knowledge.
Aquinas’s treatment of the soul’s cognition of itself is situated within his broader account of intellectual cognition. Intellectual cognition has the ‘quiddities’ of things as its object.Footnote 7 To cognize the quiddity of a thing is to know its nature or essence, which is signified by the definition of a thing in terms of genus and species.Footnote 8 In other words, it is to know what makes a thing the kind of thing it is rather than to know it in its particularity. In intellectual cognition, we are not concerned with an object insofar as it is this particular object here and now, but rather with grasping it in a more abstract and universal way. For example, I might hear and see this individual human being here and now through my senses, but then I might think about what makes this individual human being a human being in intellectual cognition. In such cognition, we are concerned with understanding the essence of humanity itself rather than the particular individuals in which it is instantiated. Thus, there is a broad sense in which questions about intellectual self-cognition may be understood as questions about how one knows one’s nature, or what Therese Cory has called ‘quidditative self-knowledge’ in Aquinas.Footnote 9
Yet when Aquinas asks whether the intellectual soul knows itself through its essence or through a species, he not asking about how an individual human knows her nature generally speaking. Instead, he is asking how a specific aspect of one’s nature is known: the nature of one’s mind or intellect. The way Aquinas formulates the question in ST I q. 87 a. 1 and DV q. 10 a. 8 invites this focus. In ST I q. 87 a. 1 the question is whether the intellectual soul knows itself through its essence and in DV q. 10 a. 8 the question is whether the mind knows itself through its essence or through some species. Further, Aquinas’s answers to these questions describe a kind of knowledge of the mind’s nature. In ST I q. 87 a. 1 co., he describes a kind of ‘universal’ knowledge of the soul as a knowledge of the nature of the mind, and in DV q. 10 a. 8 co., he describes the process of coming to know that the intellectual soul is immaterial. Again, such knowledge is not a knowledge of all that is relevant to human nature. After all, human beings are embodied, and thus understanding human nature involves understanding the human body, at least to some extent. Rather, as Therese Cory has argued, the knowledge Aquinas is focused on has to do with the aspect that differentiates us from other ensouled creatures, the intellectual aspect.Footnote 10 This is not to deny that self-knowledge, broadly construed within Aquinas’s thought, is a kind of quidditative self-knowledge concerned with knowing human nature, but Aquinas himself does not focus on this broad knowledge of human nature in his texts on self-knowledge. Rather, he is more specifically concerned with how we know the nature of our mind or intellect.
So how do we know the nature of our mind or intellect? Aquinas starts his answer to this question in ST I q. 87 a. 1 co. with the principle that ‘Everything is knowable so far as it is in act, and not so far as it is in potentiality’. Just as we see a coloured thing insofar as it is actually coloured and not just potentially coloured, so, too, our intellectual cognition depends on its object being actually intelligible in order for us to think about it. Thus, knowing the nature of our intellect depends on our intellect being actually intelligible. For Aquinas, the case of our intellect’s intelligibility is a special one because the human intellect stands between things which are actually intelligible in themselves, such as angels, and things that are not intelligible in themselves, such as material substances, such as cats.
On the one hand, Aquinas holds that immaterial substances, such as angels, in virtue of their essence existing immaterially, are intelligible to themselves without the need for a species of themselves.Footnote 11 In other words, angels know themselves through their essence because their essence is already intelligible to them or in ‘act’ in the order of intelligible things.Footnote 12 They do not need an intelligible species in addition to their essence to know themselves, but through their essence, which is actually intelligible, they know themselves. On the other hand, material things are not intelligible in themselves but only through another intellect’s activity. Humans know the natures of material things through a process that begins with sensitive experience of the material thing. For example, we begin by seeing a cat. We then proceed to abstract an intelligible species of the thing from our sense experience of it, and it is through this intelligible species that we know the nature of the material thing.Footnote 13 I abstract an intelligible species of catness from my sense experience of the cat, and this catness is the principle of my intellectual operations in which I consider what makes cats the kinds of thing they are. In short, we know the natures of material things through a species in virtue of which they are intelligible.
The case of the human mind itself is different. It is not intelligible in its essence because it is a power for understanding. As a power, its essence is to be in potentiality to intelligible objects. This is why Aquinas describes the human intellect as like ‘prime matter’ in the order of intelligibles in various places,Footnote 14 and he says in ST I q. 87 a. 1 co. that the intellect has ‘in itself the power to understand, but not to be understood, except as it is made actual’. Thus, our knowledge of our intellect is not like an angel’s knowledge of itself, which is through its essence. Instead, our knowledge of our intellect requires that our intellect be made actually intelligible. In this way, knowing the nature of our intellect is more like knowing the nature of material things. Yet Aquinas holds that our intellect is not made intelligible in the same way that material things are made intelligible. We do not abstract an intelligible species of ourselves through which we know the nature of our minds.Footnote 15 Instead, Aquinas holds that the intellect is made actually intelligible in its own act of understanding material things. That is, in abstracting an intelligible species from sense experience the active power of our intellect actualizes the passive power and thus moves itself from potentiality to actuality in the order of intelligible things.Footnote 16 Thus, our intellect is made intelligible through the same intelligible species involved in understanding other things. Once it is intelligible, we can proceed to know the nature of our intellect itself.
Aquinas further distinguishes two kinds of intellectual cognition once the intellect is actually intelligible. There is a kind of ‘singular’ or ‘proper’ cognition of one’s intellect, a cognition that it exists, and there is a kind of ‘universal’ or ‘common’ cognition of one’s intellect, a cognition of what the nature of the mind is.Footnote 17 The latter kind of cognition is often referred to by scholars as a kind of self-knowledge, while the former is referred to as a kind of self-awareness.Footnote 18 In ST I q. 87 a. 1 co. Aquinas gives an example of this ‘singular’ cognition, noting that ‘Socrates or Plato perceives that he has an intellectual soul because he perceives that he understands’. The exact nature of this self-awareness is debated by scholars, but it suffices for my purposes here to say that it is a kind of knowledge that one has a mind or intellectual aspect to oneself in virtue of one’s experience of one’s intellectual acts, as described above. Yet such cognition does not yet describe how one comes to a knowledge of the mind’s nature.
We know the nature of our mind, for Aquinas, through a ‘diligent and subtle’ inquiry into our intellectual acts. We do not know the nature of our minds through some kind of direct introspection, but, rather, we arrive at knowledge of our intellect’s nature through a process of reflecting on our intellectual activities which are grounded in our intellectual powers, which are themselves grounded in the nature of our soul. Aquinas gives a helpful example of how we arrive at such knowledge in DV q. 10 a. 8 co., where he describes how we come to know that the intellectual power or mind is immaterial.
Hence, our mind cannot so understand itself that it immediately apprehends itself. Rather, it comes to a knowledge of itself through apprehension of other things, just as the nature of first matter is known from its receptivity for forms of a certain kind. This becomes apparent when we look at the manner in which philosophers have investigated the nature of the soul. For, [1] from the fact that the human soul knows the universal natures of things, they [2] have perceived that the species by which we understand is immaterial. Otherwise, it would be individuated and so would not lead to knowledge of the universal. From the immateriality of the species by which we understand, philosophers have understood that [3] the intellect is a thing independent of matter. And from this they have proceeded to [4] a knowledge of the other properties of the intellective soul.Footnote 19 (numbered brackets are mine)
That is, one comes to know a certain aspect of one’s nature – namely, that one’s intellectual power or mind is immaterial – through considering one’s intellectual acts themselves with their objects. Whether or not one agrees with Aquinas’s conclusion, the process is clear. We begin with [1] some knowledge of the object of an act. From this we come to [2] understand the nature of the act itself. Then we come [3] to know the nature of the power for the act and ultimately, we arrive at [4] knowledge of our nature more generally speaking. This process is prone to error,Footnote 20 and what it delivers is not a knowledge that is particular to oneself. That is, what we arrive at in knowing the nature of our mind is a knowledge of one aspect of our nature, which is shared in common with all other human beings.
In sum, we can see that what Aquinas is concerned with in texts such as ST I q. 87 a. 1 and DV q. 10 a. 8 is a kind of knowledge of the nature of one’s mind. This knowledge is an instance of what might be described as a more general knowledge of one’s nature, or as quidditative self-knowledge, and for Aquinas this specific knowledge of the nature of one’s mind is acquired through a study of one’s intellectual acts.
It is worth noting here that Aquinas’s approach to self-knowledge in these questions is also situated within a historical context in which the nature of the mind and knowledge of one’s nature more broadly are seen as important kinds of knowledge. For example, Bonaventure’s Itinerarium Mentis in Deum describes a similar knowledge of one’s mind, one that starts with knowledge of the world and then proceeds from knowledge of the mind to God.Footnote 21 This progressive approach from world to mind to God is similarly found in the way Aquinas’s text situates questions about one’s knowledge of oneself in ST I q. 87 between questions of how material things are known in ST I q. 84-86 and questions of how spiritual things are known, such as angels and God, in ST I q. 88.Footnote 22 In turn, this framing plausibly traces back to Augustine’s description of his mental procession from the nature of things outside himself, to his own mind, and above to God in Book 10 of the Confessions.Footnote 23 Likewise, in Boethius’s The Consolation of Philosophy, Lady Philosophy diagnoses Boethius’s woes as stemming from having forgotten himself, not so much as an individual, but as a creature of God and in his creaturely relationship to God. In other words, it is Boethius’s forgetting certain aspects of his nature that is the cause of his troubles, rather than some fact particular to himself which he has forgotten.Footnote 24
With this context in mind, the question arises as to whether the kind of self-knowledge found in Aquinas is in line with the conception of self-knowledge many philosophers and non-philosophers are interested in today. As described above, contemporary conceptions of self-knowledge are characterized by their particularity and first-personality. That is, self-knowledge is knowledge of what is particular to oneself rather than knowledge of what one shares in common with others. Yet in Aquinas’s account of self-knowledge, what is known is not particular. It is a knowledge of something about oneself that one shares in common with all other human beings. Further, it is not clear if such knowledge is ‘first-personal’ for Aquinas. Does the method that Aquinas describes for how we know the nature of our mind deliver a first-personal knowledge of our nature? What would it even mean to know one’s nature first-personally? The next two sections distinguish two ways of knowing one’s nature and in the process articulate what it means to have a first-personal knowledge of one’s nature. I then return to Aquinas’s account in Section 4 and ask whether the method Aquinas describes provides such first-personal knowledge of one’s nature.
2. Anthropological knowledge versus self-knowledge of one’s nature
In this section, I put forward a distinction between two kinds of knowledge of one’s own nature: first, what I call self-knowledge of one’s nature; second, what I call anthropological knowledge of one’s nature. To illustrate this difference between self-knowledge of one’s nature and anthropological knowledge, consider the main character of Leo Tolstoy’s The Death of Ivan Ilyich. Set in mid-19th-century Russia, the story describes the life of a court official, Ivan Ilyich, and, ultimately, his death. Ivan lives a relatively normal life. He has ups and downs, gets married, and has a daughter. He has various successes and failures over the course of his career. By the time he is in middle age, things are going rather well for him. So he decides to refurbish his house. In the process of hanging some new curtains, he knocks his side against a piece of furniture. He experiences some minor pain at the time but thinks little of it. Over the course of weeks and months, this minor pain develops and grows, getting worse and worse. Ivan begins to obsess over the injury, and he begins to consider the prospect that he might die. Faced with death, Ivan goes through a crisis, questioning whether he has done well with his life, made the right decisions, and treated others well.
One of the most interesting aspects of Ivan’s story is that prior to his injury, Ivan had never considered his own mortality, but it is clear that he has known for quite some time that human beings are mortal. The narrator says of Ivan,
The syllogism he had learnt from Kiezewetter’s Logic: “Caius is a man, men are mortal, therefore Caius is mortal” had always seemed to him correct as applied to Caius, but certainly not as applied to himself. That Caius – man in the abstract – was mortal, was perfectly correct, but he was not Caius, not an abstract man, but a creature quite, quite separate from all others.Footnote 25
That is, Ivan knew that Caius, an individual man, was mortal because Caius was a man, and men are mortal. Yet for Ivan, Caius was not a concrete particular man, not one of his friends or family. Rather, Caius was an individual man in the abstract. Thus, Ivan recognizes that human beings are mortal and even recognizes the validity of the syllogism, such that an individual who is human is mortal. But he fails to realize this about himself, at least until he is faced with the very real, concrete possibility that he will die. In other words, Ivan appears to have anthropological knowledge (prior to his disease) of a certain fact about human nature, but he lacks self-knowledge of his own nature.
Further, this knowledge of his own mortality comes as a surprise to Ivan. As Ivan goes on to say,
If I had to die like Caius I should have known it was so. An inner voice would have told me so, but there was nothing of the sort in me, and I and all my friends felt that our case was quite different from that of Caius. And now here it is!” he said to himself. “It can’t be. It’s impossible! But here it is. How is this? How is one to understand it?Footnote 26
That is, Ivan is surprised to learn that he is mortal, despite knowing that human beings are mortal generally speaking. That this fact held for Caius was obvious, but that it held for himself less so. It seems like he should have known this about himself, but such knowledge, apparently, is not innate (no ‘inner voice’ provided him with such knowledge). Yet how exactly Ivan failed to know that he is mortal while knowing that this fact of human nature applied to Caius is not altogether clear. Investigating this failure will help clarify the distinction between anthropological knowledge and self-knowledge of one’s nature.
3. First-personal knowledge of one’s own nature
In this section, I argue that self-knowledge of one’s nature is distinct from anthropological knowledge due to self-knowledge of one’s nature being a kind of first-personal knowledge. In other words, self-knowledge of one’s nature has first-personal character which distinguishes it from anthropological knowledge. In the course of making this argument, I discuss Ivan’s failure to have self-knowledge of his nature.
In her discussion of what she calls ‘Socratic self-knowledge’, Ursula Renz provides a helpful discussion of the epistemic criteria for Socratic self-knowledge that we can apply to knowledge of one’s nature.Footnote 27 Renz argues that to have Socratic self-knowledge is not just to affirm the truth of some proposition about human nature but to acknowledge such a fact as applying to oneself in self-referential I-thoughts.Footnote 28 Thus, Renz describes the epistemic conditions for Socratic self-knowledge as involving two criteria,
(i) (S if F) is not known by S’s being F, but a posteriori; and
(ii) S knows, (s)he* is F.Footnote 29
Condition (i) is an empirical condition on Socratic self-knowledge, similar to Aquinas’s position that we know our nature through considering our actions rather than innately or by some direct introspection of our nature. In Ivan’s case, his simply being human and, thus, being mortal does not mean he automatically or easily knows that he is mortal. Instead, some effort is required to acquire this knowledge.
Condition (ii) employs terminology from Hector-Neri Castañeda to indicate not only that S knows she is F, but that S knows she herself (she*) is F.Footnote 30 Consider again John Perry’s example of the shopper who chases after someone spilling sugar, unaware that the someone spilling sugar is herself.Footnote 31 The shopper might know that she is spilling sugar insofar as she is aware that someone is spilling sugar, and the referent of this someone is herself. Yet this is not to know that she herself is spilling sugar.
In a similar way, it is not enough for S to know some fact about her nature, F, but she must know it is she herself who is F. In Ivan’s case, it is not enough that he knows that humans are mortal to know that he himself is mortal, even if his knowledge of human mortality is in fact a knowledge of himself, in virtue of being human. That is, in having this anthropological knowledge, Ivan has knowledge of himself insofar as he is an individual human falling under the scope of what he knows, but this is not self-knowledge. If Ivan’s knowledge that humans are mortal amounted to self-knowledge, then Ivan would not have been surprised when he learns that he himself is mortal in the course of his disease. Instead, Ivan’s knowledge that he himself is mortal appears to be a new instance of knowledge, distinct from his prior knowledge that humans are mortal.
Still, even if Ivan’s knowledge of human mortality is distinct from the knowledge that he himself is mortal, how does Ivan fail to know that he himself is mortal? One possibility is that Ivan lacks knowledge with first-personal content necessary to infer from his third-personal knowledge to a first-personal self-knowledge. More specifically, Ivan’s failure would seem to stem from a lack of first-personal knowledge such as ‘I am human’, which would be necessary to infer from ‘Humans are mortal’ to ‘I am mortal’. In other words, Ivan’s failure seems to stem from a failure to know, in first-personal terms, that he is human. With respect to Caius, Ivan is able to recognize that Caius is mortal because he knows that humans are mortal, and he knows that Caius is human. But in his own case, oddly, he seems to lack this knowledge that he is human. This possibility is supported by the text insofar as Ivan feels that his case is ‘quite different from that of Caius’. That is, Ivan may have never entertained the proposition that he himself is human, and thus he never thought of his situation as like that of Caius in the syllogism from his logic textbook.
That said, it is of course difficult to imagine that Ivan, or any mature human being, might lack the knowledge that they are human. That is, it is implausible that Ivan lacked knowledge with first-personal content such as ‘I am human’ and thus failed to know ‘I am mortal’. For presumably Ivan would readily affirm a proposition such as ‘I am human’ prior to his disease yet nonetheless have failed to conclude that he himself is mortal. Rather, the issue appears to be with Ivan’s failure to entertain knowledge of human nature in a first-personal way or mode. Although Ivan entertains the knowledge that humans are mortal third-personally when he affirms that Caius is mortal in virtue of Caius being human, he does not entertain that he himself is mortal in virtue of knowing that humans are mortal and knowing that he is human. Such a failure might strike us as odd, but it is not any odder than other cases in which we fail to draw inferences that seem obvious once they are drawn. For example, I might know (a) my grandfather died at 91 and (b) James Earl Jones died at 93, but not conclude (c) James Earl Jones was older than my grandfather when he died. I might not have considered the relationship between (a) and (b) and thus never concluded (c) even though the conclusion is obvious when one jointly brings the facts together.
In a similar way, I might know that humans are fallible, and I might know that I am human, but if I never consider these facts together, I may never draw the conclusion that I am fallible. In Ivan’s case prior to his disease, he might know that humans are mortal and that he is human, but without ever considering these facts together, he fails to draw the conclusions that he is mortal. Thus, even if one has anthropological knowledge, and this knowledge in fact is applicable to oneself, to have such knowledge is not the same as to entertain it as applicable to oneself first-personally. To do so is to have self-knowledge of one’s nature rather than anthropological knowledge.
4. Coming to know one’s nature as self-knowledge
Granted that there is a distinction between anthropological knowledge and a first-personal self-knowledge of one’s nature, we might ask how it is that we acquire such first-personal knowledge. In this section, I consider what is involved in coming to know one’s nature as self-knowledge. I begin by considering the suggestion that reflection on one’s own experiences is one method for acquiring self-knowledge of one’s nature. I then turn to Aquinas’s account of self-knowledge and argue that the method that Aquinas describes for knowing the nature of our mind is sufficient for arriving at a first-personal knowledge of oneself.
While Renz does not directly address how we come to have first-personal knowledge of ourselves in her account of Socratic self-knowledge, what she says about the role of reflection in early modern philosophy provides a starting point for how we might come to first-personal knowledge of our nature.Footnote 32 For example, Renz describes how the use of the first-person voice in Descartes’s Meditations on First Philosophy invites readers to reflect on their own experiences of epistemic fallibility.Footnote 33 That is, while readers may have known prior to reading the Meditations that humans are epistemically fallible, or capable of having false beliefs, Descartes’ prose prompts readers to reflect on their own experiences and thus to entertain not just the fact that humans are epistemically fallible but that oneself is epistemically fallible as well.
Reflection on one’s own experience may, therefore, provide first-personal grounds from which to proceed to a self-knowledge of one’s nature, and not just to an anthropological knowledge. Consider now Ivan’s case again. It is the experience of his disease that leads to Ivan knowing that he himself is mortal. The first way this might have happened may have been through (1) reflective investigation of his experience. Ivan gets sick, and he thinks to himself ‘I am sick. This disease of mine is life threatening. I may die’, and such reflection supports his conclusion, ‘I am mortal’. The second way this may have happened is that (2) reflecting on his experience prompts him to infer that he is mortal. While Ivan already knows that ‘Humans are mortal’ and that ‘I am a human’, the experience of his disease prompts him to infer ‘I am mortal’ from this knowledge he already possessed.
In the first case, the way Ivan arrives at knowledge that he is mortal is wholly first-personal, proceeding from first-personal thoughts and knowledge of himself that lead him to conclude that he is mortal. In the second case, the way Ivan arrives at knowledge that he is mortal is partially first-personal, proceeding from third-personal knowledge of human nature and arriving at first-personal knowledge of himself via the first-person knowledge that he is human. While both ways of arriving at knowledge of one’s own nature are possible, the key point is that in either case it is reflection from one’s own perspective that provides a first-personal basis from which one can know something about oneself as such and not just that some proposition about human nature is true.
The question is whether Aquinas’s account of how we know the nature of our mind describes a self-knowledge of our nature or anthropological knowledge. Even though Aquinas does not emphasize the need for reflection in his account of self-knowledge, the idea that reflection on our own actions might provide a first-personal grounds for our knowledge can be seen in the way Aquinas contrasts the kind of knowledge angels and devils have of an individual human’s soul from an individual’s knowledge of her own soul in DM q. 16 a. 8, as well as the role of what was described as ‘singular’ or ‘proper’ cognition of oneself in ST I q. 87 a. 1 and DV q. 10 a. 8.
In DM q. 16 a. 8, Aquinas argues that while devils can know the nature of an individual’s soul better than any human being, they lack a knowledge of an individual’s cogitationes cordium or ‘secret thoughts’. Therese Cory interprets Aquinas as arguing here for a distinction between devils as having knowledge of the soul’s nature and the forms which may exist within the soul versus a human individual’s first-person perspective on her interior thoughts insofar as the individual herself uses such forms.Footnote 34 In forwarding her interpretation of Aquinas, Cory, rightly, I think, highlights DM q. 16 a. 8 ad. 7, where Aquinas responds to an objection that argues that because devils have a greater knowledge of the soul than humans do, and our thoughts are in our soul, then devils must know our thoughts.Footnote 35 In reply, Aquinas maps the difference between a devil’s knowledge of an individual’s thoughts and an individual’s own knowledge of her thoughts onto the distinction between self-knowledge which is ‘common’ or ‘universal’, as described above, and a kind of self-awareness which Aquinas describes as ‘proper’ or ‘singular’.Footnote 36 That is, angels or others might know the nature of the soul or human nature just as well, if not better, than we do, but only the individual herself has a knowledge of her thoughts and actions from a first-person perspective as an agent.
That is, an angel might know that the human mind is immaterial, for example, but the angel cannot know this through a personal reflection on human thought. Only the individual herself can reflect on the experience of her own mind, and thus arrive at the knowledge that her mind is immaterial. An individual’s perspective on her thoughts provides her with a first-personal basis from which she can proceed in reflective investigation of her thoughts to know that her mind is immaterial. In other words, when one reasons from an experience of one’s thinking, ‘I am thinking about cats’, to draw conclusions such as ‘The object of my thought is universal’ and ‘My act of thought must be immaterial’ and ‘My soul itself must be immaterial’, one develops a knowledge of one’s own nature that is first-personal, i.e., a self-knowledge of one’s own nature.
In contrast, while angels might know that the human soul is immaterial, their knowledge is not a knowledge of human nature that can be entertained first-personally. They do not arrive at such knowledge from the first-person experience of human thought but from intelligible species of human nature that exists in their own mind.Footnote 37 Yet, as described in Section 1, we do not know the nature of our intellect by having an intelligible species of our nature but through the intelligible species that we abstract from sense experience. This intelligible species actualizes our intellect, and thus our intellect is intelligible to us in our reflection on it, from our perspective as the one thinking. Thus, although Aquinas distinguishes two kinds of intellectual self-cognition, these two kinds of self-cognition are related in an important way. The self-awareness of our minds that we have through the experience of our intellectual acts provides a first-personal ground for the quidditative knowledge of our intellect’s nature and, thus, a self-knowledge of our own nature.
5. Conclusion
Contemporary conceptions of self-knowledge are particular and first-personal. They are about knowing what is particular to oneself and knowing it as about one’s very self. In contrast, Aquinas’s account of self-knowledge is focused on how we know our own nature, and, more specifically, how we come to know the nature of our minds. Thus, it might appear that Aquinas’s conception of self-knowledge is quite different from contemporary conceptions. While it is true that Aquinas’s conception lacks the particularity of contemporary conceptions, it is a self-knowledge insofar as it is a first-personal conception of how we know our nature. This first-personal knowledge of one’s nature derives from reflecting on experiences of oneself, and we can see the first-personal aspect of Aquinas’s account in the way that self-awareness of one’s actions provides a first-personal ground for reflective self-investigation into one’s nature. In other words, what is required for our knowledge of our nature to be self-knowledge is a reflection on its truth in our own lives, a reflection on the experience of our own thoughts, actions, and feelings from which we arrive at a self-knowledge of our own nature.
