as above

1. Reminder:
Arguments against concept innatism
• Are given by concept empiricists such as Locke, Hume, Berkeley
• These arguments also (mostly) apply against knowledge innatism:
– There are no such concepts/no such knowledge and we do not possess them/it –
‘innate concepts’ are ‘empty’, the terms meaningless – ‘From what impressions is
that supposed idea derived?’ - Hume
– Such concepts/knowledge can be re-defined as based on experiences – we can
explain them arguing that they are derived from our experience, learned.
– Locke’s arguments against innatism:
» there is no universal consent/ agreement about such concepts/ knowledge
» It is trivial to say that innate knowledge is just ‘the capacity to know’
» and we can explain how we possess such knowledge in other ways (by
redefining them as based on experience).
– Innatism’s reliance on the non-natural: weird metaphysics (Plato!) or God always
gets invoked to explain where such concepts/knowledge come from.
– [Such knowledge is merely analytic] – (Hume) – it does not add to our knowledge
of the world because it is (trivially) to do with definitions.

2. Reminder: the difference between ideas or
concepts and knowledge
• Ideas or concepts = mental contents, notions,
something that you think. John Locke:
"whatsoever is the Object of the
Understanding when a Man thinks."
• Knowledge = propositions that are true,
believed, justified – hence, something that
you know for sure because it can be
articulated into statements.

3. Reminder: a priori, a posteriori knowledge
• A priori knowledge: can
be known to be true
independently of
sensory experience –
‘known without leaving
the sofa’.
• A posteriori knowledge:
confirmed only by
sensory experience.
Video game tester (true!)
En route to the a priori. (Or should that be The Priory?)

4. The Origins of Knowledge
Knowledge Empiricism

5. Syllabus moment
Green = we’ve covered this already
• Knowledge empiricism: all synthetic knowledge is a posteriori (Hume’s
‘fork’); all a priori knowledge is (merely) analytic.
• Issues, including:
– knowledge innatism (rationalism): there is at least some innate a priori
knowledge (arguments from Plato and Leibniz)
– knowledge empiricist arguments against knowledge innatism: alternative
explanations (no such knowledge, in fact based on experiences or merely
analytic); Locke’s arguments against innatism; its reliance on the non-natural
– intuition and deduction thesis (rationalism): we can gain synthetic a priori
knowledge through intuition and deduction (Descartes on the existence of
self, God and the external world)
– knowledge empiricist arguments against intuition and deduction: the failure of
the deductions or the analytically true (tautological) nature of the conclusions
– arguments against knowledge empiricism: the limits of empirical knowledge
(Descartes’ sceptical arguments).

6. Concept Empiricism, Concept Innatism
Knowledge Empiricism, Knowledge Innatism
• CE vs CI
– ALL ideas are derived only from experience OR SOME key
ideas are innate to us.
• KE vs KI:
– ALL synthetic knowledge is a posteriori
(=contingent but useful), ALL a priori
knowledge is merely analytic or
tautologous (=necessarily true, but dull).
OR
– SOME synthetic knowledge is a priori:
there is synthetic a priori knowledge (=
both necessary and useful).
Hume’s Fork:
ALL knowledge
is either
synthetic a
posteriori OR
analytic a priori
KEY
EMPIRICIST
CLAIM

7. Reminder: Subject, Copula, Predicate
• Propositions take the form:
X is Y
– X is the SUBJECT
– ‘is’ asserts connection…hence COPULA
– Y is a QUALITY…or PREDICATE

8. Analytic Statements
• An analytic statement is a proposition where
– Kant: ‘The subject contains the predicate’
– Hence the subject and the predicate contain the same
information
– such as…?
• ‘Vixens are female’
• ‘Bachelors are unmarried’
– so…a ‘definition in terms’…
– true merely by virtue of the meaning of the words
concerned…

9. Tautologies and the Tautologous
• In other words…a tautology
• a statement that
– adds nothing to your understanding of the world
– but merely restates the meaning of a word
– or defines it
• To call a statement tautologous is to say that it is
a tautology
• So (Empiricist claim!) all analytic statements are
tautologous  they teach us nothing new
• Tautologies are trivial, uninteresting, empty

10. Synthetic statements
• A synthetic statement is a proposition where
– the subject and the predicate do not contain the same
information
– such as…?
• ‘Malabar will win the Grand National’
• ‘Bachelors are a good idea as wedding guests’
• So, descriptive of the world…
• …they teach us something new – are interesting, ‘vivid’,
therefore.
• But (Rationalists!) cannot be certain or necessary.
– Synthetic statements could always be imagined to be different.
– It is a contingent fact that Mount Everest is the world’s highest
mountain; it does not have to be so.

11. Which is which?
• Thinking of ‘a priori’ and ‘a posteriori’
knowledge…
– Which kind of knowledge would tautologies/ analytic
statements put into words?
– Which kind of knowledge would synthetic statements
put into words?
• Key Empiricist Claim: ‘Hume’s Fork’: ALL
knowledge is either synthetic a posteriori OR
analytic a priori.

12. (Analytic) a priori knowledge
Question, Answer, Reply?
Q. Why might Descartes be interested in
knowledge that has an a priori/rational
justification? (That is: knowledge that is
true independently of any particular
experience e.g. maths, logic, ethics)
A dull but necessary profession…
A. (Meditation One): such knowledge
seems certain compared to the error-
prone senses.
R. But (problem): is all a priori knowledge
merely analytic? True by definition;
certain, yet empty; dull but necessary.

13. (Synthetic) a posteriori knowledge
Question, Answer, Reply?
That’s right. Most of the internet: the
opposite of dull but necessary.
Q. Why might empiricists be interested in
knowledge that has an a posteriori
justification? (That is: knowledge
dependent on the world to be true?)
A. Such knowledge seems vivid, useful,
applicable compared to truths-by-
definition.
R. But (problem): can a posteriori
knowledge be certain? It may be vivid,
but it is also contingent.

14. (Synthetic) a posteriori knowledge
Question, Answer, Reply?
That’s right. Most of the internet: the
opposite of dull but necessary.
Q. Why might empiricists be interested in
knowledge that has an a posteriori
justification? (That is: knowledge
dependent on the world to be true?)
A. Such knowledge seems vivid, useful,
applicable compared to truths-by-
definition.
R. But (problem): can a posteriori
knowledge be certain? It may be vivid,
but it is also contingent.

15. Starter
Answers to Cloze exercise on
Knowledge Empiricism and Knowledge Innatism
Knowledge empiricists claim that all knowledge can be divided into one of two
kinds. This claim is sometimes referred to as ‘Hume’s Fork’, after David Hume,
who argued that all knowledge was either of Matters of Fact or Relations of
Ideas.
Knowledge empiricists claim that all synthetic knowledge (of ‘Matters of Fact’)
is a posteriori, hence contingent but useful, whereas all priori knowledge is
merely analytic or tautologous, so necessarily true, but trivial.
In contrast, Knowledge Innatists claim that Hume’s Fork is incorrect and some
synthetic knowledge is a priori. Hence there is knowledge that is both
necessary and useful.
Examples of synthetic a priori knowledge might include mathematical truths, or
Kantian Categories such as causation, substance, quantity, quality.

16. Starter
Write some sentences about knowledge and statements…

17. Knowledge Empiricism: ‘Hume’s Fork’
all synthetic knowledge is a posteriori; all a priori knowledge is
(merely) analytic
Hume argues that all knowledge can be divided into only
two kinds:
All the objects of human reason or enquiry may naturally
be divided into two kinds, to wit, Relations of Ideas, and
Matters of Fact. Of the first kind are the sciences of
Geometry, Algebra, and Arithmetic ... [which are]
discoverable by the mere operation of thought ... Matters of
Fact, which are the second object of human reason, are not
ascertained in the same manner; nor is our evidence of
their truth, however great, of a like nature with the
foregoing.
• Draw and label Hume’s Fork. What characterises each
kind of knowledge?

18. The Key Claim of Empiricism
• Hume’s Fork: ALL knowledge of synthetic propositions
is a posteriori; ALL knowledge of analytic propositions
is a priori.
– Truths not known by definition or logic alone can only be
acquired through the senses. These truths are contingent.
– We can come to know some truths by definition by
reflecting on our sensations. But these a priori truths are
not world-shaking.
• (Of course, if we can find SOME synthetic a priori or analytic a
posteriori knowledge, then Empiricism is wrong…)