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Texts for “Epistemology Past and Present,” John Carriero, UCLA
TEXT 1) Spinoza, TdIE, §§ 19-20:
1. There is the perception we have from hearsay, or from some sign conventionally
agreed upon.
2. There is the perception that we have from casual experience; that is, experience that
is not determined by the intellect, but is so called because it chances thus to occur [casu
sic occurrit], and we have experienced nothing else that contradicts it, so that it remains
in our minds unchanged.
3. There is the perception we have when the essence of a thing is inferred from another
thing, but not adequately. This happens either when we infer a cause from some effect
or when an inference is made from some universal which is always accompanied by
some property.
4. Finally, there is the perception we have when a thing is perceived through its essence
alone, or through knowledge of its proximate cause.
All these I shall illustrate with examples. By hearsay alone I know [scio] the date of my
birth, who my parents were, and things of that sort, which I have never doubted. By
casual experience I know [scio] that I shall die; this I affirm because I have seen that
others like me have died, although they have not all lived to the same age nor have died
from the same disease. Again, by casual experience I know [scio] that oil has the
property of feeding fire, and water of extinguishing it. I know that a dog is a barking
animal and man a rational animal. And it is in this way that I know [novi] almost
everything that is of practical use in life.
TEXT 2) Spinoza, 2p41:
Cognition [cognitio] of the first kind is the only cause of falsity; cognition of the second
and third kind is necessarily true.
TEXT 3) Leibniz, Monadology, § 28:
Men function like beasts [i.e., lower animals] insofar as the connections among their
perceptions come about only on the basis of memory, resembling empirical physicians
who have mere practice without theory. We are all mere empirics in three-quarters of
our actions. For example, when one expects a sunrise tomorrow, one acts as an empiric,
seeing that this has always been so heretofore. Only the astronomer judges this by
reason. [Rescher, 106-107]
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PNG, § 5:
Men too, insofar as they are empirics, that is to say, in three-fourths of their actions, act
only like beasts. For example, we expect day to dawn tomorrow because we have
always experienced this to be so; only the astronomer predicts it with reason, and even
his prediction will ultimately fail when the cause of daylight, which is by no means
eternal, stops. But reasoning in the true sense depends on necessary or eternal truths,
as those of logic, number, and geometry, which make the connections of ideas
indubitable and their conclusions infallible. Animals in which such consequences cannot
be observed are called beasts, but those who know these necessary truths are the ones
properly called rational animals, and their souls are called spirits.
TEXT 4) Spinoza, at the end of 2p28dem:
Therefore, these ideas of affections, insofar as they are related only to the human mind,
are like conclusions without premises; that is, as is self-evident, confused ideas.
TEXT 5) Leibniz’s notes on Descartes’s Principles:
On Article 5. There can be no doubt in mathematical demonstrations except insofar as
we need to guard against error in our arithmetical calculations . . . [Loemker, 384]
On Article 13. I have already observed, on Article 5, that the errors which can arise from
defective memory or attention and which can also occur in arithmetical calculations
even after a perfect method has been found, as in numbers, have been mentioned here
to no purpose, since no method can be devised in which such errors are not to be
feared, especially when the reasoning is long drawn out. So one must resort to criteria.
For the rest, God seems to be called in here merely as a kind of display or showpiece,
not to mention that strange fiction or doubt as to whether we are not led to err even in
the most evident things [evidentissimis], which should convince no one because the
nature of evidence [natura evidentiae] prevents it and the experiences and successes of
the whole of life witness against it.
TEXT 6) Spinoza, 2p47s:
That men do not have as clear knowledge of God as they do of common notions arises
from the fact that they are unable to imagine God as they do bodies, and that they have
connected the word God with images of things which they commonly see; and this they
can scarcely avoid, being affected continually by external bodies. Indeed, most errors
result solely from the incorrect application of words to things. When somebody says
that the lines joining the center of a circle to its circumference are unequal, he surely
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understands [intelligit] by circle, something different from what mathematicians
understand. Likewise, when men make mistakes in arithmetic, they have different
figures in mind from those on paper. So if you look only into their minds, they indeed
are not mistaken; but they seem to be wrong because we think that they have in mind
the figures on the page. If this were not the case, we would not think them to be wrong,
just as I did not think that person to be wrong whom I recently heard shouting that his
hall had flown into his neighbor’s hen, for I could see clearly what he had in mind.
[Cf. Spinoza, TdIE, § 79:
Hence it follows that it is only when we do not have a clear and distinct idea of
God that we can cast doubt on our true ideas on the grounds of the possible existence
of a deceiving God who misleads us even in things most certain. That is, this can happen
only if, attending to the knowledge [cognitionem] we have of the origin of all things, we
find that there is nothing to convince us that he is not a deceiver, with the same
conviction that we have when, attending to the nature of a triangle [the “gold”
standard], we find that its three angles are equal to two right angles. But if we do
possess such knowledge of God [cognitionem] as we have of a triangle, all doubt is
removed. And just as we can attain such knowledge [cognitionem] of a triangle although
not knowing [sciamus] for sure whether some arch-deceiver is deceiving us, so too we
can attain such knowledge [cognitionem] of God although not knowing [sciamus] for
sure whether there is some arch-deceiver. Provided we have that knowledge, it will
suffice, as I have said, to remove all doubt that we may have concerning clear and
distinct ideas.]
TEXT 7) Spinoza
2p43: He who has a true idea knows at the same time that he has a true idea,
and cannot doubt its truth.
From 2p43s: For nobody who has a true idea is unaware that a true idea involves
absolute certainty. To have a true idea means only to know a thing perfectly, that is, to
the utmost degree. Indeed, nobody can doubt this, unless he thinks that an idea is some
dumb thing like a picture on a tablet, and not a mode of thinking, to wit, the very act of
understanding [nempe ipsum intelligere]. And who, pray, can know [scire] that he
understands [intellegere] something unless he first understands it? That is, who can
know that he is certain of something unless he is first certain of it? Again, what standard
of truth can there be that is clearer and more certain than a true idea? Indeed, just as
light makes manifest both itself and darkness, so truth is the standard of both truth and
falsity.
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TEXT 8) Descartes, from the Fifth Meditation:
Not only are all these things [viz. continuous quantity, its extension, sizes,
shapes, positions, and local motions] known and transparent to me when regarded in
this general way, but in addition there are countless particular features regarding shape,
number, and motion and so on, which I perceive when I give them my attention. And
the truth of these matters is so open and so much in harmony with my nature, that on
first discovering them it seems that I am not so much learning something new as
remembering what I knew before; or it seems like noticing for the first time things which
were long present within me although I had never turned my mental gaze [obtutum
mentis] on them before. [¶4; 7:63-64; 2:44]
TEXT 9) From Burman’s notes of a conversation with Descartes:
[Descartes] . . . For since the cause is itself being and substance, and it brings
something into being, i.e., out of nothing (a method of production which is a prerogative
of God), what is produced must at the very least be being and substance. To this extent
at least, it will be like God and bear his image.
[Burman] But in that case even stones and suchlike are going to be in God’s
image.
[Descartes] Even these things do have the image and likeness of God, but it is
very remote, minute and indistinct. [5:156; 3:340]
TEXT 10) From Barry Stroud’s The Significance of Philosophical Scepticism:
That conclusion [external-world skepticism] can be avoided, it seems to me, only
if we can find some way to avoid the requirement that we must know that we are not
dreaming if we are to know anything about the world around us. But that requirement
cannot be avoided if it is nothing more than an instance of a general procedure we
recognize and insist on in making and assessing knowledge-claims in everyday and
scientific life. We have no notion of knowledge other than what is embodied in those
procedures and practices. So if that requirement is a ‘fact’ of our ordinary conception of
knowledge we will have to accept the conclusion that no one knows anything about the
world around us. [p. 31]
TEXT 11) Locke, Essay Concerning Human Understanding:
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If by this Enquiry into the Nature of the Understanding, I can discover the Powers
thereof; how far they reach; to what things they are in any Degree proportionate; and
where they fail us, I suppose it may be of use, to prevail with the busy Mind of Man, to
be more cautious in meddling with things exceeding its Comprehension; to stop, when it
is at the utmost Extent of its Tether; and to sit down in a quiet Ignorance of those
Things, which, upon Examination, are found to be beyond the reach of our Capacities.
TEXT 12) Hume, A Treatise Concerning Human Nature:
. . . any hypothesis, that pretends to discover the ultimate original qualities of human
nature, ought at first to be rejected as presumptuous and chimerical (p. xvii)
But if this impossibility of explaining ultimate principles should be esteemed a
defect in the science of man, I will venture to affirm, that ’tis a defect common to it with
all the sciences . . . (p. xviii)
TEXT 13) Descartes, from Meditation IV:
Now when I do not perceive clearly and distinctly enough, then if I abstain from
bringing my judgment to bear, it is clear that I act correctly [recte] and am not deceived.
But if in such cases I either affirm or deny, then I am not using my free will [libertate
arbitrii] correctly [recte]. If I go for the alternative which is false, then obviously I shall be
in error; if I take the other side, then it is by pure chance [casu quidem] that I arrive at
the truth, and I shall still be at fault since it is clear by the natural light that the
perception of the intellect should always precede the determination of the will. [¶12;
7:59-60; 2:41]
TEXT 14) Kant, A Critique of Pure Reason:
The famous Locke . . . because he encountered pure concepts of the understanding in
experience, also derived them from this experience, and thus proceeded so
inconsistently that he thereby dared to make attempts at cognitions that go far beyond
the boundary of all experience. David Hume recognized that in order to be able to do
the latter it is necessary that these concepts would have to have their origin a priori. But
he could not explain at all how it is possible for the understanding to think of concepts
that in themselves are not combined in the understanding as still necessarily combined
in the object, and it never occurred to him that perhaps the understanding itself, by
means of these concepts, could be the originator of the experience in which its objects
are encountered, he thus, driven by necessity, derived them from experience (namely
from a subjective necessity arisen from frequent association in experience, which is
subsequently falsely held to be objective, i.e., custom); however he subsequently
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proceeded quite consistently in declaring it to be impossible to go beyond the boundary
of experience with these concepts and the principles they occasion. The empirical
derivation, however, to which both of them resorted, cannot be reconciled with the
reality of the scientific cognition a priori that we possess, that namely of pure
mathematics and general natural science, and is therefore refuted by the fact. [B127128]