PHIL 3120: American Philosophy
Dr. Robert Lane
Lecture Notes: Wednesday January 7, 2015




[2.] Charles Sanders Peirce.


·         1839-1914

·         Peirce grew up in Cambridge, Massachusetts (the location of Harvard University), which by the 1800s was an important center of American intellectual activity.

·         His father was Benjamin Peirce, a professor of mathematics at Harvard and the most distinguished mathematician in America.

·         He graduated from Harvard in 1859, after which he worked for the U.S. Coast and Geodetic Survey.[1] He then returned to college, graduating from Harvard’s Lawrence Scientific School with a degree in chemistry in 1863. As we will see, his training as a scientist informs his work in philosophy.

·         He began lecturing and publishing in philosophy in 1863.

·         He taught at Johns Hopkins University (Baltimore, MD) from 1879 to 1884 as a part-time lecturer in logic. This was his only regular position with an academic institution.

·         Peirce was forced to resign from both the U.S. Coast and Geodetic Survey and Johns Hopkins by a combination of circumstances, including his difficult personality, circumstances surrounding his second marriage (it was known he had had an affair with his second wife before they were married), and his having made powerful enemies, including Charles Eliot (an instructor of Peirce’s at Harvard, and president of Harvard from 1869 until 1909) and Simon Newcomb (an influential Canadian-American scientist who worked behind the scenes to prevent Peirce from getting tenure at Johns Hopkins and to derail Peirce’s application for an important research grant from the Carnegie Institute). Peirce never held an academic position again after leaving Johns Hopkins.

·         In 1887, he retired to Milford, PA. There he spent the rest of his life in poverty, writing almost constantly on philosophical and scientific issues.

·         Biographer Joseph Brent has argued that Peirce was a victim of bipolar disorder. Another scholar, David Pfeifer, has argued that Peirce’s behavior was more consistent with the form of autism known as Asperger syndrome.


Of the three classical pragmatists—Peirce, James, and Dewey—Peirce is the least widely known. The reasons for this include[2]:

·         he never held a permanent academic position, so he had very few students to disseminate his ideas;

·         he was relatively isolated from academia for the last few decades of his life; and

·         his work is reputed to be difficult and inaccessible because of (1) his use of symbolic logic and (2) his use of difficult terminology which he himself coined.


Another reason his work is difficult to understand is that he was a system-builder. Like Aristotle and Kant, he wanted to build an all-encompassing philosophical system.


But he never articulated a complete and definitive statement of that system. This can make studying Peirce very frustrating.


There is also the following:

·         Peirce scholars disagree about which of his writings are the most important for understanding his thought.[3]

·         Peirce wrote a tremendous amount of philosophical material, some of which was published in his lifetime, but the majority of which was not and still hasn’t been.



[2.1.] Peirce vs. Descartes.[4]


Our first reading from Peirce is his 1868 article “Some Consequences of Four Incapacities.”


It is the second of three papers by Peirce published in the Journal of Speculative Philosophy from 1868 to 1869. These papers are referred to collectively as “the cognition series”:


·         “Questions Concerning Certain Faculties Claimed for Man”

·         “Some Consequences of Four Incapacities”

·         “Grounds of Validity of the Laws of Logic: Further Consequences of Four Incapacities”


One thing Peirce does in these papers is criticize the account of philosophical inquiry put forward by René Descartes (1596-1650; French rationalist) in his Meditations on First Philosophy.[5]



[2.1.1.] Descartes: Method of Doubt, Quest for Certainty.


One of Descartes’ goals in the Meditations was to show that skepticism is false.


skepticism (df.): the view that knowledge is impossible; human beings never actually know anything.


In other words, Descartes was trying to show that human beings do have knowledge.


His strategy was to search for beliefs that are epistemically certain and build up from there.


epistemic certainty (df.): S is epistemically certain that p iff S believes that p and S cannot possibly be mistaken in that belief; epistemic certainty requires the impossibility of error.


This is very different from


psychological certainty (df.): a feeling that a belief one has must be true, e.g., when I see and feel the desks in this room and come to believe that the room contains desks, I feel certain that there are desks in the room.

·         It is possible to feel certain that p even if it is false that p; e.g., a gambling addict might feel certain that she is going to win the next hand of blackjack, even if in fact she is not; a religious fanatic who feels certain that she knows God’s will.


It is as if Descartes’ current beliefs are an unstable building, and he wants to knock the entire thing down so that he can identify a stable foundation of epistemically certain belief upon which he can build something new.


How did he intend to identify these certain beliefs? Descartes employed a test to discover which beliefs are certain, i.e., which are stable enough to serve as a foundation for the rest of his knowledge.


This test is his “Method of Doubt”:

1.      Try to think of a reason to doubt a belief. It doesn’t have to be a plausible reason… it just has to be possible.

2.      If you can come up with a reason to doubt it—any reason at all, no matter how unlikely that reason is to be true—then you set that belief aside. It is not epistemically certain, and so it cannot be part of a stable foundation.

3.      Whatever beliefs are left “pass” the method of doubt test and are epistemically certain: they cannot be false.

·         There is no guarantee that there will be any beliefs that pass the method of doubt test.


At one point, Descartes thinks that he has found a reason to doubt just about everything:

it is possible that there is “some malicious demon of the utmost power and cunning” deceiving us about anything and everything.[6]


The Method of Doubt test asks: since it is possible that there is an all-powerful demon who has the power to fool us about anything, is there any belief which we can hold with certainty?


But, says Descartes, here is at least one thing about which an evil demon could not fool me:


1. I am having thoughts and experiences.


If it seems to you that you are thinking or having an experience, then you are thinking or having an experience. What your thoughts or experience represents to you may be completely false, but it is still the case that you are having an experience.


And this leads to another belief in which I can be certain:


2. I exist.


If I did not exist, it would be impossible for me to experience or think anything.


Among our ideas is the idea of God. But (says Descartes) this is different than our ideas of desks and books and clouds ... etc. The idea of God is the idea of a perfect being—and a being that does not exist is not perfect. So Descartes thinks he has yet another belief that is immune from doubt:


3. God exists.


And this is the key to dispelling doubt about the bulk of our beliefs regarding the world outside our minds. Since God is perfect, he is not a deceiver, and he would not create us in such a way as to allow us to be completely deceived. So he can be certain that


4. I am not being fooled by an evil demon.


Once he has identified a group of beliefs that (he says) are certain, he asks: what it is about these beliefs that makes them certain?


His answer: his grasp of the belief that he is an existing thing that thinks is so clear and distinct that that belief cannot possibly be false.


So Descartes identifies this as the criterion of certainty: any belief that is clear and distinct (like the belief that he is a thinking thing) is certain.


From this basis, Descartes went on to argue for various claims about the world outside his mind.






[2.1.2.] Four Characteristics of Cartesianism.


Peirce opens “Some Consequences of Four Incapacities” with a list of four characteristics of Cartesianism (p.70):


C1.  “philosophy must begin with universal doubt”.


C2.  “the ultimate test of certainty is to be found in the individual consciousness”.


C3.  In philosophy, it is acceptable to support claims with “a single thread of inference depending upon inconspicuous premises.”


C4.  There are “absolutely inexplicable” facts—facts that can never be explained—“unless to say ‘God makes them so’ is to be regarded as an explanation.”


Peirce rejects all four claims of Cartesianism and counters each claim with a claim of his own (pp.70-72):


P1. “We cannot begin with complete doubt.”


P2. “We individually cannot reasonably hope to attain the ultimate philosophy which we pursue; we can only seek it, therefore, for the community of philosophers.”


P3. Philosophy should “proceed only from tangible premises which can be subjected to careful scrutiny, and . . . trust to the multitude and variety of its arguments than to the conclusiveness of any one.”


P4. The supposition that something is “absolutely inexplicable . . . is never allowable.


We will examine these one by one.



[2.1.3.] The Method of Doubt is Impossible.


C1.  Philosophy should begin with universal doubt.


P1.     “We cannot begin with complete doubt.”


The Method of Doubt involves deliberate doubt, in that Descartes tries to doubt as much as he can.


But according to Peirce, genuine doubt is not deliberate or voluntary. Any alleged doubt that is deliberate or voluntary is bound to be fraudulent. The “doubt” that Descartes’ method relies on is no such thing—it is fake doubt.


Real doubt (and real belief, too) are involuntary. We cannot doubt at will, as Descartes claims to be doing.[7]

So we cannot begin inquiry (whether philosophical, scientific, or any other kind) by deliberately doubting everything. Descartes’ Method of Doubt test is impossible. We cannot actually do what it recommends.


How should we begin inquiry? Peirce says: we must begin with the beliefs we already have.


We must begin with all the prejudices which we actually have when we enter upon the study of philosophy. These prejudices [beliefs that we already possess] are not to be dispelled by a maxim, for they are things which it does not occur to us can be questioned. Hence this initial skepticism will be a mere self-deception, and not real doubt; and no one who follows the Cartesian method will ever be satisfied until he has formally recovered all those beliefs which in form he has given up. It is, therefore, as useless a preliminary as going to the North Pole would be in order to get to Constantinople (now called Istanbul, in the nation of Turkey] by coming down regularly upon a meridian [a line of longitude] (70-71).[8]


Part of what Peirce is getting at here is this… Each of us already has a large number of genuine beliefs, and there is no point in searching for a starting point for inquiry other than what we already genuinely believe. In particular, there is no point in searching for an epistemically certain starting point.


On Peirce’s view, it is no coincidence that Descartes winds up back with his old beliefs (e.g., that God exists, that the mind is not the same thing as the body) by the end of the Meditations—because his claim to have given those beliefs up was “mere self-deception.” He never really gave them up in the first place.


A person may, it is true, in the course of his studies, find reason to doubt what he began by believing; but in that case he doubts because he has a positive reason for it, and not on account of the Cartesian maxim. Let us not pretend to doubt in philosophy what we do not doubt in our hearts (71, emphasis added).



Stopping point for Wednesday January 7. For next time, study all of the lecture notes from this week’s class meetings, and read (again) pp.69-72. We will discuss the remaining principles of Cartesianism and Peirce’s responses to each of them during the next class.



[1] This agency of the federal government is now known as the National Geodetic Survey (


[2] Cornelis de Waal, On Peirce, ch.1.


[3] Christopher Hookway (Peirce, Routledge, 1985, p.7) observes: “Where the student of Descartes or Kant can undertake to understand a number of central texts, any attempt to specify a canon of central Peircean texts is likely to be controversial.”


[4] For more on this see Haack’s “Descartes, Peirce and the Cognitive Community,” in Eugene Freeman, ed., The Relevance of Charles Peirce, La Salle, IL, Monist Library, 1983, 238-263. See also Lesley Friedman’s “Doubt & Inquiry: Peirce and Descartes Revisited,” Transactions of the Charles S. Peirce Society 35 (4), 1999, 724-746.


[5] Descartes’ Meditations remains one of the most widely read philosophical works of the modern period. You probably read this in Introduction to Philosophy, and it is required reading in Modern Philosophy. For more on Descartes, see Gary Hatfield, "René Descartes", The Stanford Encyclopedia of Philosophy (Spring 2015 Edition), Edward N. Zalta (ed.), forthcoming URL = <>.


[6] Meditations, in Selected Philosophical Writings, trans. J. Cottingham, R. Stoothoff and D. Murdoch.p.79. The 20th century analogue of Descartes’ evil demon story is: it is possible that you are not really a college student but instead a brain in a vat--a brain kept alive through artificial means and whose experiences are generated by a super-computer to which it is connected. A similar scenario is depicted in the film The Matrix.


[7] Peirce makes and elaborates on these points about doubt and belief a number of times in his later writings. E.g., see 1877’s “The Fixation of Belief,” p.115 of your textbook (EP 1:115, CP 5.376) and 1905’s “What Pragmatism Is” (EP 2:336, CP 5.416; not in your textbook).


[8] EP 1:29, CP 5.264.

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