Defending Descartes’s Dictum

I’ve been told that Descartes’s dictum, cogito ergo sum (“I think, therefore I am”) was nothing more than an epic failure in reasoning. And that by this same reasoning you could demonstrate your own existence from your body odor (I stink, therefore I am). Or that all that Descartes’s dictum really can demonstrate is that there is thinking going on, but not that there is a thinker who is thinking- a self who belongs to the indexical ‘I’. After reading Descartes a bit for myself, and studying a bit more about transcendental arguments, I’ve come to reject those simplistic rejections of Descartes’s dictum. This post is a brief defense of the cogito.

You may also want to check out this clip from my conversation with Dr. James Anderson on this very topic.

Cogito Ergo Sum (I think, therefore I am) – Descartes’ Dictum
The phrase, “I think, therefore I am” has become famous through the teachings of the rationalist French philosopher, René Descartes, as well as, among other things, the popular ‘80s movie, Bladerunner. As a rationalist, Descartes was skeptical about sense experience due to its lack of certainty- our senses can always deceive us after all. I mean you can put a stick in the water and it appears to be bent but when you pull it back out, it’s not bent after all. Your senses deceived you!

As a Rationalist, Descartes’ method of arriving at incorrigible knowledge disparages all rival criteria and sources of knowledge until reason alone prevails as king- but not reason simpliciter, as other Rationalists might argue- rather, Descartes builds his whole system on a single rational proposition. After all, if our senses can deceive us- even if only on occasion- then they certainly can’t provide us with, well, certainty… If even the best of human reasoners can be wrong in their reasonings, then appeals to human authority can’t provide certainty either. Worse still, since we can be deceived by our own dreams which present themselves as reality when we’re in them, it would appear that even our own reason, simpliciter, leaves us on shaky foundations at best. The apparent impotency of empiricism, authority, and naïve common sense concerning certainty led Descartes to doubt everything that he could doubt until he found “that which presented itself to [his] mind so clearly and distinctly, that [he] would have no occasion to doubt it.”[2]

So, Descartes employed this method of doubt and applied it to everything he could until he hit rock bottom: certainty at last! Descartes finally achieved cognitive rest with his phrase “I think, therefore I am”- for doubt though he tried, he felt he couldn’t consistently doubt his own existence. And I think he’s right!

In Part Four of Descartes’s A Discourse on the Method, he reveals the bedrock that he has been drilling towards, his indubitable truth, his foundation of certainty: cogito ergo sum. Popularly translated “I think, therefore I am”, Ian Maclean argues in an explanatory note that a better gloss is the performative: “I am thinking, therefore I exist.”[3] But why does Descartes think that this dictum can suffice as thee indubitable first principle for his philosophy? Well, because when subjected to all the skeptical doubts, counterexamples, and attacks which laid waste to all the other first principles, cogito ergo sum prevails unfazed. The cogito is even shown to be the very foundation for the skeptical doubts themselves, for to doubt is to think, and if I am thinking then I exist, so I can never truly doubt that I exist.

In his Principles of Philosophy, we find one of Descartes’ clearest expositions of his dictum,

As long as we are doubting, we cannot doubt that we exist; and this is the first thing we know when philosophizing methodically. Thus by rejecting all those things that we can in any way doubt and even pretending that they are false, we easily suppose that there is no God, that there are no heavens or bodies, and that we ourselves have no hands or feet, nor indeed any body at all – but not, however, in such a way that we, who think these thoughts, are nothing. For it is impossible for us to think that whatever thinks does not exist during the very time that it thinks. Therefore [despite the most extravagant assumptions, we cannot prevent ourselves from believing that this inference] this knowledge, ‘I am thinking, therefore I exist’, is the foremost and most certain that occurs to anyone who philosophizes methodically.” (Meditations and Other Metaphysical Writings, Penguin Classics, pg. 113-114)

Here we see that Descartes’ cogito, ergo sum depends on a similar phrase, “dubito, ergo sum”, or “I doubt, therefore I am”. For if Descartes doubts that he thinks, he still has to think in order to doubt, and if he thinks then he exists. So, he cannot consistently doubt that he exists without engaging in performative inconsistency and thus, self-defeat.

Descartes believed that he had found certainty and from this principle he concluded that he was “a substance whose whole essence or nature resides only in thinking”[4]. This “I” he deduced was the immaterial soul which existed apart from the material body and can survive the death of said body. From this conclusion it was a short jaunt for Descartes to employ his own Ontological Argument for God’s existence: “of necessity there must be some other, more perfect being upon whom I depended and from whom I had acquired all that I possessed.”[5]

Some have argued that by this same reasoning, one could say “I stink, therefore I am” along with other “hilarious” examples. But these criticisms miss Descartes’ rationalistic emphasis. For Descartes, sense experience can always be deceived, thus I stink, therefore I am can always be subjected to doubt. Do you really stink, or is there a malfunction in your olfactory receptors? Similarly, Descartes says that to say “I see” or “I walk, therefore I am” can also be doubted since we often have dreams where we are walking or seeing things but we aren’t actually seeing or walking. But, even if we’re dreaming or being deceived by our senses or even systematically deceived by an evil demon in all our thinking, we are still thinking in in our deception, thus we still exist even if we are being deceived. So, while the possibility of deception precludes other sources of knowledge from being our bedrock, deception itself presupposes thinking, which presupposes a thinker, ‘I’.

So, now we see why thinking takes priority over against sense experiences, but some claim that “thinking” is really all that Descartes’s dictum can demonstrate, rather than the stronger claim that “I am thinking”. In his latest book, Richard Swinburne explains why this argument against Descartes is mistaken:

“The eighteenth-century thinker Georg Lichtenberg famously objected that all that Descartes knows [via his cogito ergo sum argument] is that ‘there is thinking going on’, not that some person is doing the thinking. But that objection seems mistaken. ‘Thinking’ is a property, and there can only be an instance of some property if some substance has that property. And Descartes does not know merely that someone somewhere is thinking, he knows who it is that is doing the thinking-himself.” (Are We Bodies or Souls?, 73).

So, as Swinburne argues, the property of thinking needs a substance to instantiate it, thus if there is thinking going on, then there is a substance which that property of thinking inheres. Swinburne, following Descartes, goes on to argue from the cogito to a more fleshed out substance dualism, i.e., that we are both bodies and souls, material and immaterial, but essentially, we are an immaterial rational soul. Again, I agree.

Because I have direct awareness of the thinking that’s going on in my consciousness. I have no direct awareness of your conscious experiences, but I do have direct awareness of mine. So, I am perfectly justified in saying that I am thinking. Do I have knowledge of the unity of my experience over time? Well, perhaps not, based on the cogito, but at this moment I know that I exist because I am thinking and a presupposition of thinking is existence of a substance in which the property of thinking subsists. Even if I were to doubt that I am an “I”, I must presuppose that I exist in order to doubt my own existence. So, I exist and am unable to doubt that I exist or that I am and “I”. So, “I” is an informative designator for me, even though it may be an uninformative designator for you.

But as James Anderson notes in the video at the beginning of this post, one need not go as far as full-blown substance dualism to feel the force of the cogito.

In his Internet Encyclopedia of Philosophy entry, Adrian Bardon explains that Descarte’s dictum is a powerful transcendental argument, that is, an argument which takes a given, an uncontentious, or an intrinsic phenomena of human experiences and seeks to show the necessary conditions which make that experience possible. Bardon notes that,

“A few scholars have observed that Descartes’s “Cogito, ergo sum” argument can be re-conceived as a transcendental argument:

(1) I think.
(2) In order to think “I think,” it is necessary to exist.
(3) Hence, I exist.

This argument meets the criteria for a transcendental argument: it takes a fact about one’s mental life as a premise, adds that some extra-mental fact is a necessary condition of the truth of that premise, and concludes that the extra-mental fact holds. This argument would turn on the claim that the statement, “I do not exist” (or better, the proposition that no one exists) is performatively self-defeating in the sense that the fact of its performance counts as conclusive evidence against its truth. That is what connects the mental fact (I am thinking about whether I exist) to the relevant extra-mental fact (I exist). Regardless of how this argument might fail in some other respect, it presupposes neither verificationism nor idealism in closing the gap between the internal and the external.”

So, a necessary condition of thinking, is a subject, a thinker, who is engaging in that act. To deny that you are thinking is self-defeating, likewise, to doubt your own existence presupposes your existence, and is like wise self-defeating. So, from the phenomena that “I am thinking” I can know that “I exist” or I am- even to doubt one’s own existence is evidence that one exists!

Now, at this point, some have found an overwhelming similarity between Descartes’ cogito, ergo sum and Augustine’s si falor, sum. Augustine spilled much ink refuting the skeptics of his day, chief of which were, ironically, the Academics or Academicians, i.e., those who studied in Plato’s Academy. This is ironic because Plato spent so much of his time refuting the Sophists and Skeptics of his own day, only to have his own school turn towards skepticism itself.

In responding to the Academicians, Augustine says, “Where these truths are concerned I fear none of the arguments of the Academicians when they say: “What if you’re in error [concerning your existence]?” If I’m in error, I exist [si fallor, sum]. Someone who doesn’t exist surely can’t be in error! In light of this fact, I exist if I’m in error. Therefore, since I exist if I’m in error, how can I be in error about my existing, when it’s certain that I exist if I’m in error? Because I would have to exist if I were in error, then, even if I were in error, I am therefore undoubtedly not in error about knowing that I know. For just as I know that I exist, so too I know this very fact – that I know it.” (The City of God 11 .26, in Against the Academicians and The Teacher, Hackett, pg. 162).

I admit that I’m swayed by those who think Descartes straight up ripped off Augustine with not even so much as a footnote giving credit. But whereas Augustine used this line of reasoning as a refutation of skepticism concerning the self, Descartes used it as his bedrock foundation for building an entire epistemology, and indeed his entire philosophy. Whereas Augustine was firm in his allegiance to God, Descartes found it easy to “suppose there is no God”- a sentiment that my hero Cornelius Van Til most vehemently opposed. Indeed, Descartes’ own contemporaries found this troubling, as Pascal is attributed with saying, “I cannot forgive Descartes: in his whole philosophy he would like to do without God; but he could not help allowing him a flick of the fingers to set the world in motion; after that he had no more use for God.” (Pensées, Penguin Classics, pg. 330). But, I digress.

As I reflect on the Descartes’s dictum, I find that I’ve been moved from antagonistic to enthusiastic. Mind you, I am not a full blown Cartesian, but I came into this line of thought hand in hand with Pascal, who is attributed with saying “I cannot forgive Descartes: in his whole philosophy he would like to do without God; but he could not help allowing him a flick of the fingers to set the world in motion; after that he had no more use for God.”[6] But after reading the Descartes for myself, I find that Descartes’s project mirrored that of Augustine in the Soliloquies, who sought to know God and the soul, nothing more, nothing whatsoever.[7]

However, Descartes’ cogito ergo sum, the foundation for his project, has been charged as fallacious throughout the years, which threatens his endeavor to know God and the soul, and his goal of finding certainty. But it seems that most attacks don’t take into account the transcendental nature of Descartes’ dictum. Descartes isn’t seeking to prove his existence in a straightforward direct argument, rather, his cogito is an indirect argument, a transcendental argument which argues that his existence is the precondition of his thinking, therefore if he’s able to think at all, he must exist, and so he cannot doubt that he exists. I think Descartes’ dictum works as a transcendental proof for the existence of the self – and perhaps even a transcendental proof for the existence of God (!): “However much the best minds choose to investigate this matter, I do not believe that they will be able to furnish any argument which is sufficient to remove this doubt, unless they presuppose the existence of God.” (33). But credit for the cogito should probably go to Augustine, who, debating the Academicians, defeated their full blown skepticism by saying “si fallor sum[9], that is “If I’m in error, I exist.”[10]

So, it appears that the cogito is the proximate starting point of all thought Who’s thinking? If there is thinking going on, it’s someone’s thinking. If I have direct awareness of thinking going on, it’s my thinking. I cannot doubt that I am thinking because to doubt is to think. I can’t doubt that it is I who is thinking because the “I” is presupposed in all of my thoughts. So it seems that “I think” is an incorrigible belief for me. It’s a transcendental argument not a deductive argument. Starting with an incorrigible aspect of human experience, in this case the fact that I am thinking, we reason to what must be the case in order for that experience to be what it is.

But while the cogito is the proximate starting point of all thinking and knowledge, it ought not be seen as the ultimate starting point or reference point of all thinking and knowledge, that place belongs not to “I am” but to the Great I AM. Though we must begin with the cogito temporally, ultimately, our cogito presupposes God’s Cogito. Van Til is right to claim that “for man self-consciousness presupposes God consciousness.” The cogito is our temporal and proximate starting point which presupposes the great I AM- I think therefore God is. but this is a subject for another post… I think.


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