Transcript July 14th as a powerpoint file (requires Powerpoint)

Today’s Lecture
• Preliminary comments on George Berkeley
• George Berkeley
• Preliminary comments on Bertrand Russell
Preliminary comments on George
Berkeley
• George Berkeley was born in 1685 in (what is now
the Republic of) Ireland and died in 1753 (in
Oxford, England, while visiting his son).
• He is, perhaps, the greatest Irish philosopher and he
was a devote Christian (member of the Church of
Ireland).
• Toward the end of his life he was appointed Bishop
of Cloyne (which is now in the Republic of Ireland).
Preliminary comments on George
Berkeley
• Berkeley is famous for his Idealism, which contrasts
with Materialism.
• Materialism is the view that matter is the basic stuff
out of which the universe is made.
• Idealism is the view that the basic stuff is ideas, yes
mental entities, instead of Matter.
• Locke had a basically materialistic view of the
natural universe, with the caveat that animals like us
had souls (that are not material).
Preliminary comments on George
Berkeley
• Berkeley’s Idealism is largely motivated by his
perceptions that Materialism was a threat to
Christian theism and a source of skepticism about
objects really existing in the world.
• Importantly, then, Berkeley really believes that
objects exist (in the world). It just so happens that
they don’t, they can’t, exist independent of mind, be
it ours’ or God’s. So the world of sensible objects is,
in an importance sense, not external in the way
thought of by materialists.
Preliminary comments on George
Berkeley
• Berkeley believes that there are only active
spirits (or perceivers) and passive sensible
things in the cosmos. What’s more passive
sensible things only exist as that which is
perceived by the active spirits (be they God,
angels, animals or humans).
• Particular things are only sets of ideas that
are seen to constantly accompany each
other.
Preliminary comments on George
Berkeley
• This will have a peculiar consequence for
Berkeley’s view of science.
• On the one hand, our common views of
causality are false. After all, ideas don’t
cause ideas per se, and because objects in
the world appear to effect change in other
objects (in the world), that change has to be
explained in ways other than how we
commonly view causality.
Preliminary comments on George
Berkeley
• Berkeley is an occasionalist. This means
that the regularities in the world, that we
commonly associate with causal powers in
external objects, events or processes, are
maintained by God’s ongoing active
intervention in our mental experiences.
Without such divine intervention, there
would be no regularities, and no recurring
sensible ideas.
Preliminary comments on George
Berkeley
• It is Berkeley’s belief that Idealism is more
consistent with Empiricism than Materialism.
• In our readings Berkeley will argue that Locke’s
treatment of primary qualities, and his contentions
that these are best explained as caused by external
objects, fail.
• As this is Locke’s only way of getting beyond the
curtain, or veil, of ideas to the world he thinks is
beyond our minds, this, if Berkeley is successful,
will effectively trap the empiricist behind the curtain
or veil.
Berkeley’s view in our readings
• Berkeley contends that neither the secondary nor the
primary qualities can exist without minds (such
qualities cannot be separated from clearly affective
qualities, or they are in other ways clearly perceiver
relative [e.g. you cannot think of primary qualities
without associated secondary qualities]).
• He also contends that our knowledge and discourse
about sensible objects (e.g. tables, chairs, snow, et
cetera) is limited to, or reduces to, our talk of their
primary and secondary qualities.
• As these qualities cannot exist without minds, nor
can the associated sensible objects.
Berkeley’s view in our readings
• He also attacks the very idea of extant objects that
cannot be perceived but which underlie our
perceptions (these objects are supposed by
materialists to be the objective causes of our ideas,
and thus sensible objects).
Berkeley’s view in our readings
• Argument (1): Consider a material substratum to be that
which underlies those (perceptual) qualities they are said to
support.
• To describe them as objects which support (perceptual)
qualities is to imply that they have properties that allow
them to do their supporting (of said [perceptual] qualities).
• But if properties require support from a substratum this will
require the positing of another substratum to support those
properties that support said (perceptual) qualities.
• This will again repeat itself at this (lower) level of
abstraction, ad infinitum. But this is absurd (FP, pp.216-17).
Berkeley’s view in our readings
• Argument (2): As we cannot conceive of such
objects (we cannot conjure up an idea of such an
object without an associated perceptual quality), we
cannot (sensibly) talk of them.
• As these (imperceptible) objects are beyond our ken,
we also have no (good) reasons to think they
exist...we cannot have thoughts about them at all
(FP, p.217).
Berkeley’s view in our readings
• Argument (3): The fundamental commitment of materialists
seems to be to external objects whose actual qualities
produce in us ideas that are their copies (i.e. copies of the
real external qualities inhering in the real external object).
• These objects are fixed, with qualities that are also fixed and
do not actually undergo change corresponding to changes in
our own spatial locations.
• It seems that our ideas, as copies of these fixed qualities,
nevertheless undergo constant change.
• As these ideas are inconsistent with one another, and each is
said to equally arise from our interactions with the external
objects, it seems we have no reason to think any one or
several of them copies of the original qualities (see FP,
pp.220-21).
Berkeley’s view in our readings
• Argument (4): All perceptible qualities are ideas, and so
mind dependent. If there are material objects external to the
mind they must be imperceptible.
• Ideas are held to be copies of the original external
imperceptible qualities.
• But imperceptible qualities cannot be intelligibly said to
resemble perceptible qualities without themselves being
perceptible qualities.
• Only perceptible qualities can be like perceptible qualities.
• Thus, only ideas can be like other ideas.
• Thus ideas cannot be copies of original external
imperceptible qualities (see FP, p.221).
“The First Dialogue”
• The first thing to notice in this reading is the way in
which Philonous ‘dings’ Hylas for suggesting a
definition of global epistemological skepticism that
has consequences Hylas does not intend. In doing so
Philonous dialectically provides an internal criticism
of Hylas’ opening salvo (see FP, p.203).
• The second thing to notice is the style of argument
adopted by Philonous. It is, in the first place,
dialectical. Second, it involves showing internal
inconsistencies in the views of one’s opponent. It is
an example of internal (as opposed to external)
criticism.
“The First Dialogue”
• In the second column on page 203 of your FP we
have the first stages of the discussion. Before it can
be decided whether Philonous can be properly
described as a skeptic of sensible objects existing in
the world we need to agree on what is a sensible
object.
• Hylas first definition is “Those things which are
perceived by the senses” (FP, p.203).
• This is tightened to “those only which can be
perceived immediately by sense” (FP, 203) because
otherwise such mediated ‘objects’ as God would
count as sensible objects.
“The First Dialogue”
• Hylas also admits that it is by our reason
that we infer the existence of causes in the
external world for our ideas, rather than
directly perceiving them through the senses
(FP, p.204).
• All that we directly perceive through our
senses, according to Hylas, are such
qualities as color, taste, sound, shape, and
texture (FP, pp.203-04).
“The First Dialogue”
• Given that these is no-thing directly perceived by
the senses but these qualities, Hylas must hold that
sensible objects are no-thing more than these
perceived qualities or cluster of qualities (FP,
p.204).
• Hylas now makes a distinction between existence
and perception. It is one thing for some-thing to
(really) exist, it is quite another for that thing to be
perceived (or experienced through the senses).
“The First Dialogue”
• Hylas is now asked to classify heat according to his
admitted ontology (theory of what (really) exists).
• Given that heat is directly perceived by the senses,
it qualifies as a sensible object.
• Hylas also concedes that as a ‘real’ sensible object,
heat both exists and is perceived.
• Hylas also makes no ontic distinction between
degrees of heat ... each degree of heat is equally real
(FP, p.204).
“The First Dialogue”
• This has an unfortunate implication, however.
Since extreme heat causes extreme pain, which
is also immediately perceived by the senses and
associated with heat, this train of reasoning
implies that the sensible object Hylas is directly
sensing is partially constituted by pain.
• But this is absurd, as Hylas’ believes that this
object must be material, and thus incapable of
feeling pain (FP, p.204).
• Something, then, must give.
“The First Dialogue”
• Hylas now suggests (at the bottom of the second column on
page 204 of your FP) that we need to distinguish extreme
heat from the sensation of pain that accompanies it.
• Philonous challenges this distinction on the following
grounds:
• (1) At the time in which we have one simple idea of a fire
by putting our hand near it, we immediately perceive both
extreme heat and pain (FP, p.205).
• (2) Hylas concedes that he cannot think of an extreme
sensation without an accompanying pain or pleasure.
• (3) Hylas concedes that he cannot think of a pain or pleasure
without an accompanying sensation of a secondary quality
(FP, p.205).
“The First Dialogue”
• Hylas concedes Philonous argument has shown that
extreme heat cannot exist without a mind. This
means it cannot exist in a material substance
external to the mind.
• Heat, in its extreme form, has no real existence,
according to Hylas (FP, p.205).
• Hylas points out that this does not show that heat
does not really exist in a non-extreme form in an
external object. After all, it is only extreme heat that
is constantly associated with pain.
“The First Dialogue”
• Philonous tries to show that a gentle heat (or warmth) is
constantly associated with pleasure, from which would
follow his previous argument with ‘pleasure’ substituted for
‘pain’. Hylas however contends that gentle heat is neutral
between pain and pleasure, and so avoids the conclusions of
the previous argument (FP, p.206)
• In exasperation Philonous moves on to the quality of cold in
the hopes of making the point in a way that Hylas cannot
but concede shows that secondary qualities only exist in
minds (FP, p.206).
• Incidentally this shows an interesting limitation to this form
of philosophical reasoning.
“The First Dialogue”
• Since Hylas concedes that Philonous’ argument for
extreme heat works for extreme cold, Philonous
turns to a discussion of “a lesser degree of cold”
(FP, p.206).
• Hylas concedes two points to Philonous before they
begin their next stage of the discussion.
• (i) A doctrine is false if it “leads a man into an
absurdity” (FP, p.206).
• (ii) The same thing cannot be said to possess two
apparently exclusive qualities such as heat and cold
(FP, p.206).
“The First Dialogue”
• You can now see where this argument is going to go.
• Philonous will persuade Hylas that the same thing
can be warm or cold by considering a pale of water
and the sensations felt by both hands as one puts
them in the pale.
• Since Hylas cannot, without absurdity, contend that
the same object has two exclusive properties or
qualities, he must concede that neither heat nor cold
exists in a material substance independent of, or
external to, the mind (FP, p.206).
Preliminary comments on Bertrand
Russell
• Bertrand Rusell was born in 1872 and died in 1970
at the ripe old age of 98.
• He was both a mathematician and philosopher.
• Perhaps his best known work is in philosophy of
language, though he also wrote extensively on
epistemology.
• He was, I think without little doubt, one of the most
important of the British philosophers of the
Twentieth Century (and there have been a number of
important British philosophers in the Twentieth
Century).
Preliminary comments on Bertrand
Russell
• Russell’s biography testifies, in large part, to his
determination to live a philosophical life.
• Views that informed his political activities in the
public sphere, be it his atheism, peace advocacy
or views on the equality of women, were views
he took the time to philosophically defend.
• Perhaps most admirably, he was imprisoned on
two occasions for his peace advocacy.
Preliminary comments on
Bertrand Russell
• Perhaps four things characterize Russell’s
epistemology: (1) It was analytic, (2)
rigorously empiricist, (3) internalist, and (4)
foundationalist.
• Russell was one of the best and earliest
proponents of analytic philosophy. This
philosophical school is characterized by its
insistence on conceptual analysis as the
primary vehicle of doing philosophy.
The Problems of Philosophy:
Appearance and Reality
• Some terms that Russell uses require explanation (see FP,
p.247).
• Sense data: Arguably, this is what Locke called ideas. They
are the content of our immediate perceptions. They are what
Russell considers to be immediately known form our senses.
• Sensation: Is the immediate awareness of sense data.
• Physical object: This is the real object, beyond our sense
data.
• Matter: This is the collection or sum of all physical objects.
The Problems of Philosophy:
Appearance and Reality
• “Is there any knowledge in the world which
is so certain that no reasonable man could
doubt it?” (FP, p.245)
• The first line of this chapter reveals
important things about Russell’s view of
knowledge, or at the very least reveals
important things about the knowledge of
concern to this book of philosophy.
• Note the echoes of Descartes.
The Problems of Philosophy:
Appearance and Reality
• This chapter nicely sets up the distinction already
discussed by Descartes and Locke (and by us) that
leads to problems concerning our knowledge of the
external world, namely the distinction between
appearance and reality.
• Russell agrees with Locke that we infer the
existence of external objects from the experience
arising from our senses (FP, pp.246-47).
• In fact, I think Russell nicely articulates what Locke
was saying.
The Problems of Philosophy:
Appearance and Reality
• “Thus it becomes evident that the real table,
if there is one, is not the same as what we
immediately experience by sight or touch or
hearing. The real table, if there is one, is not
immediately know to us at all, but must be
an inference from what is immediately
known” (FP, p.247 [emphasis his]).
The Problems of Philosophy:
Appearance and Reality
• “When, in ordinary life, we speak of the colour of
the table, we only mean the sort of colour which it
will seem to have to a normal spectator from an
ordinary point of view under usual conditions of
light. But the other colours which appear under other
conditions have just as good a right to be considered
real; and therefore, to avoid favouritism, we are
compelled to deny that, in itself, the table has any
one particular colour” (FP, p.246).
The Problems of Philosophy:
Appearance and Reality
• Note something that may be important in what
Russell claims here. He suggests (though remember
he has actually argued for this suggestion) that our
ordinary claim to know the color of a table
presupposes a set of standards covering the truth
conditions for the claim. What’s more, these truth
conditions contain specifications regarding the
noetic health of the putative knower, perhaps her
level of education or degree of socialization, her
location and the conditions of viewing.