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Transcript
A Course in Consciousness
This is a course in questioning and in
seeing, not in believing.
Question everything (but not
necessarily in class)!
Believe nothing!
See directly!
Why are we dissatisfied with life?
• We feel separate from
our thoughts, feelings,
and body sensations.
• We think they should
not be the way they
are…
• …so we try to change
them.
• The more we try to
change them, the
more separate from
them we feel.
We feel separate from the world…
• We think it should
not be the way it
is…
• …so we try to
change it.
• The more we try to
change it, the more
separate from it we
feel.
We feel separate from Reality
• What is Reality,
anyway?
• We yearn and
yearn to know it.
• Yet, the more we
yearn for it, the
farther we seem to
be from it.
Who/what is this “I” that is trying so
hard?
• Maybe “I” is what we should investigate!
• But, that seems too hard and it might
make our heads hurt. (We’ll do that later.)
• Let’s start with something “easy”, like
philosophy and physics.
• That might give us some answers…
• …and maybe it will help us answer the
hard questions!
The concept of objective reality
• Objective reality is assumed to exist whether or not
it is being observed.
• The existence of separate objects is assumed to be
verifiable by observation, at least in principle.
• The predominant feature of all objects is that
they are by definition separate from each other.
• This means that separation is a basic assumption…
• …so the observer-object is assumed to be separate
from the observed-object.
• We will see later that these are all nothing but
assumptions!
Objective reality (cont.)
• In addition to the assumption of
separation, objective reality has three
other components:
– 1) Observation of an object or its absence.
– 2) Communication of the observation to
others.
– 3) Agreement with others on the existence or
nonexistence of the object.
Still more on objective reality
• Agreement is required because…
• 1) We must agree on the definition of the object
• 2) The existence or nonexistence of the object
must be confirmed by at least one other
observer. If it is not confirmed, the existence or
nonexistence of the object is indeterminate.
• 3) The object exists only for those who agree
that it exists. For those who disagree, it doesn’t
exist!
But, what is it that is being
observed?
• All of our observations of objects are
nothing but sense impressions (one for
each of the five senses).
• But, sense impressions are not objects!
The mind takes sense impressions and
forms mental images of objects from them.
• Thus, if there are no sense impressions,
there are no objects, and if there are no
mental images, there are no objects.
An object is nothing but a concept!
• A concept is the result of the mental process of
separating and naming.
• If something is separate from something else,
and if we refer to it by name, it is nothing but a
concept. (A name may be simply a pronoun, like
“you”, “me, “him”, “her”, “this”, “that”, “they”, “it”).
• All objects are separate from each other. We (as
objects with names) give them names in order to
communicate with others (as objects with
names).
• Thus, all objects are nothing but concepts.
Why do we think objects exist if
they are not being observed?
• We think that objects exist if they are not
being observed because we have been
taught that they do!
• But how can we verify that an object exists
except by observing it?
• If we think we can verify an unobserved
object’s existence by its effects on objects we
are observing, how can we verify that those
effects come from the unobserved object if
the unobserved object is unobserved?
The philosophy of materialism
(pure objectivity)
(Earliest materialists: Atomists Leucippus, Democritus, and
Epicurus: 460-270 BC)
• Everything is assumed to be matter (or, at least, it is
governed by physical law).
• Space and time are assumed to be objective—they
are assumed to exist whether or not there is an
observer.
• Matter is assumed to be objective—it is assumed to
exist whether or not there is an observer.
• If consciousness exists, it is assumed to be an
epiphenomenon of matter with no independent
existence of its own.
Personalized statement of
materialism
• “I am a body.”
• Do you agree with this statement? If so,
are you all of the body or just parts of it?
• Which parts are you? Which parts are you
not?
• Where in the body are you?
• What is this “I” that is a body?
• Is it material?
• Is it conscious?
Other questions about materialism
• Which, if any, of the following are
conscious, and what is the evidence for it?
– Cats and dogs?
– Plants?
– Microbes?
– Self-reproducing protein molecules
(e.g., prions)?
– Inanimate objects (e.g., rocks)?
The philosophy of Cartesian dualism
(objectivity plus subjectivity)
(René Descartes, 1596-1650)
• Descartes proposed that mind and matter are
two fundamental, independent substances.
• He proposed that a mind is an indivisible,
conscious, thinking entity without physical
size or spatial location.
• He proposed that a body is a divisible object
that has physical size, i.e., it occupies space.
• He proposed that mind and body can interact
with each other.
Personalized statement of
Cartesian dualism:
• “I am a mind and I have a body”.
• This implies that “I” am subjective but the body is
objective.
• (Note that the complementary statement, “I am a
body and I have a mind”, is a personalized
statement of materialism.)
• Do you agree with this statement of Cartesian
dualism? If so, are you all of the mind or just
parts of it?
• Which parts are you? Which parts are you not?
• “Where” in the mind are you?
Other questions about Cartesian
dualism
• Similar questions as for materialism:
Which objects have minds and which do
not:
• Animals?
• Plants?
• Microbes?
• Prions?
• Rocks?
The philosophy of idealism
(pure subjectivity)
Plato (380 BC), Berkeley (1710), Kant (1781)
• Idealism is a Western philosophy that proposes
that everything is Mind, and…
• …there is nothing but Mind.
• This is similar to the Eastern teaching of
nonduality (next slide).
• Whereas, idealism is purported to describe
Reality (assuming that Reality can be
described),…
• …Nonduality is taught as a pointer to Reality
(Reality cannot be described, only pointed to).
The teaching of nonduality
(pure subjectivity)
Ramana Maharshi (1879-1950), Nisargadatta Maharaj
(1887-1981), Ramesh Balsekar (1917-2009), Francis
Lucille (1944-), Greg Goode (1943-)
• Nonduality teaches that Awareness is all there
is.
• Awareness does not exist in space. Space is a
concept in Awareness.
• Since space is only a concept in Awareness,
objects, which supposedly occupy space and
are separate in space, are also nothing but
concepts in Awareness.
• Therefore, separation is also only a concept in
Awareness.
A mind in nonduality
• Remember: A concept is the result of the mental
process of separating and naming.
• Hence the rule: If it is separate and can be
named or pointed to, it is only a concept.
• Example: A mind is a concept because it is
thought to be separate from other minds.
• “My” mind is a concept consisting of the
concepts of “my” thoughts, feelings, emotions,
sensations, and perceptions.
• “Your” mind is a concept consisting of the
concepts of “your” thoughts, feelings, emotions,
sensations, and perceptions.
Questions about minds
• If separation is only a concept, how can
there really be separate minds?
• If there are not really separate minds, why
am “I” not aware of “your” thoughts?
• If there are not really separate minds, why
do “you” and “I” seem to be
communicating with each other?
• The ultimate questions: Who are the “I”
and the “you”?
Classical physics
Isaac Newton (1643-1727)
• Classical physics was
assumed to be both
materialistic and objective.
Consciousness was not part of
the theory.
• Classical objects were
assumed to have separate,
independent existences
whether or not they were being
observed.
• They were assumed to have
definite properties, such as
position, velocity, and
orientation whether or not
these were being observed.
These properties were
assumed to have no intrinsic
uncertainties.
Classical physics (cont.)
• Classical objects were assumed to be acted
upon by classical forces such as
electromagnetism and gravity.
• The laws of classical physics were
deterministic. This means that the state of
the universe in the future is assumed to be
completely determined by the state of the
universe in the present, which is assumed
to be determined by the state of the
universe in the past.
Questions about classical physics
• How might our lives be different if there were no
external objective reality but we did not know it?
• What if we did know it?
• How might our lives be different if the world were
deterministic but we did not know it?
• What if we did know it?
• Suppose we really accepted the principle of
determinism as truth. How would we feel about
our own feelings, decisions, and actions?
• About other people’s feelings, decisions, and
actions?
In the late 1800s, problems arose
with classical physics
• It could not explain certain experiments (e.g.,
blackbody radiation, the photoelectric effect, and
line spectra of atoms).
• After 3 decades of trying to make classical
theory work, physicists replaced it with quantum
theory in the 1920s. (Why did it take so long?)
• In order to get a theory that successfully
explained the experiments, physicists had to
abandon the basic assumption that objective
reality consisted of separate, independently
existing, observable objects!
The development of quantum
theory
• Like classical theory, quantum theory was formulated to
describe only measurements on objective processes.
• At first, it was intended to describe only measurements
on microscopic processes, but now it is assumed to
describe measurements on all physical processes, from
those of elementary particles to those of the entire
universe.
• It is the only physical theory we have at the present time.
(Classical physics is a good approximation for
macroscopic masses.) If it is incorrect, we have as yet
no other theory to replace it.
• In every direct and indirect experimental test of quantum
theory so far, the basic principles have never been
shown to be invalid.
What does quantum theory describe?
• Quantum theory is a theory of observation.
• Most physicists accept that quantum theory correctly
predicts the probability that an observation will yield a
specific result (e.g., the probability that a position
measurement will yield a specific position). This is called
the instrumentalist interpretation.
• But, both predictions and observations can be made without
requiring preexisting objects. For example, consider the
following three cases:
• Case #1: If we are not observing an object, how can we
assume that it exists?
• Case #2: If we are making an observation, how would we
know we are making an observation on a preexisting object?
An observation need not refer to a preexisting object (e.g., a
thought, feeling, fantasy, imagination, dream).
• Case #3: If we assume that a preexisting object exists, how
can we verify its existence? The only possible way is to make
an observation….but see Case #2.
Does quantum theory say anything
about objective reality?
• Classical physics was the study of the properties of what
was assumed to be preexisting objects.
• Objects were assumed to be preexisting because it was
thought that they could be perceived directly with the
human senses, and the mind told us that the objects
existed even when we did not perceive them.
• However, quantum theory predicts microscopic
phenomena that cannot be perceived directly with the
human senses…
• …and it is not obvious how to relate the predictions to
the behavior of preexisting objects, if there are any.
• An interpretation is needed for this…
• …but the interpretation is not self-evident.
In fact…
• …there are many interpretations of
quantum theory, almost as many as there
are those who interpret it.
• We still don’t know if there is a “correct”
one…
• …and, if there is, we don’t know what it is!
Are there any quantum objects here?
• Measured probabilities of
the locations of “iron
atoms” forming a circular
ring of peaks surrounding
probabilities of locations
of “electrons” forming
continuous circular rings.
The “surfaces” are
densely packed point
measurements. But, only
positions were
measured, not objects!
Richard Feynman (1918-1988)
(Brilliant, creative, iconic theoretical physicist, and
bongo drummer)
• “…I think I can safely
say that nobody
understands quantum
mechanics.” The
Character of Physical
Law (1960).
There are three general types of
interpretations of quantum theory
• Interpretation in terms of purely
objective reality (ontological
interpretation).
• Interpretation in terms of Cartesian
dualism (objectivity plus subjectivity).
• Interpretation in terms of purely
subjective reality (epistemological
interpretation).
The Copenhagen interpretation
Born, Heisenberg, Schrödinger, Bohr (1925-1927)
• Even though the Copenhagen
interpretation is supposed to be the
“orthodox” interpretation, there is
widespread disagreement on it.
• Some physicists think it is purely objective.
• Some physicists think it is partly objective
and partly subjective.
• And a few (very few) think it is purely
subjective.
In the Copenhagen interpretation…
• Space and time are assumed to be
objectively real.
• The universe is assumed to be split
between a quantum wavefunction and a
macroscopic observer or measurement
device.
• Prior to an observation, the wavefunction
is assumed to exist over all space.
Elementary description of a
physical wave
• A physical wave is a
traveling oscillation.
• Physical waves carry
energy and momentum.
• Examples: Water waves
and electromagnetic
waves. Simulation at:
http://www.surendranath.org/Applets.html
• However, the quantum
wavefunction is not a
physical wave. It is a
purely mathematical
wave.
Big paradox: The wavefunction is
purely mathematical, but is assumed to
be objectively real!
• The wavefunction is assumed to exist whether or
not there are observations.
• It represents the probability (not the certainty)
that a specific result (e.g., a position) will be
obtained if a specific type of observation (e.g., of
position) is made.
• It describes all of the possible results (e.g., all of
the possible positions) that could be obtained ,
but cannot predict which result will actually
be obtained.
Wavefunction collapse
• At the moment of observation, the
wavefunction is assumed to change
irreversibly from a description of all of the
possibilities (e.g., of position) that could be
observed to a description of only the result
that is observed.
• This is called wavefunction reduction, or
wavefunction collapse.
The next observation
• After an observation and wavefunction collapse,
a new wavefunction emerges.
• It represents all of the possibilities that are
allowed by the previous observation.
• Another observation results in another wave
function collapse, etc.
• In this interpretation, a sequence of
observations results from a sequence of
wavefunction collapses.
• Without wavefunction collapse, there are no
observations.
After 85 years, wavefunction
collapse is still not understood
• It could be a result of conscious observation
(not explainable by physics).
• It could be a result of the wavefunction of the
system interacting with the wavefunction of a
measuring device plus its environment (called
decoherence→technical difficulties).
• It could be a result of a modification of the
Schrödinger equation, which is the basic
equation of quantum physics (called objective
collapse→technical difficulties).
Daring prediction!
• Wavefunction collapse will never be
understood because it starts with an
impossible assumption, that the
wavefunction is objective when every
physicist knows that it is just a
mathematical formula!
Hidden-variables interpretations
David Bohm (1917-1992)
• Particles are assumed to
exist as classical particles
whether or not they are
observed (purely
objective interpretation).
• They are assumed to be
acted on by the classical
forces, such as
electromagnetism and
gravity.
• In addition, the particles
are assumed to be acted
on by a quantum force,
which is derived from the
quantum wavefunction.
No collapse in hidden-variables
theory, however, it is nonlocal
• In classical theory, there are no fasterthan-light effects. Therefore, all effects are
local.
• In hidden variables theory, classical
particles (real particles) are always
present, so no collapse is required.
• However, hidden variables theories are
intrinsically nonlocal because the quantum
force acts at all points in space
simultaneously.
Many-worlds interpretation
(Hugh Everett, 1930-1982)
•
•
•
•
•
Many-worlds is a partly objective
and partly subjective
interpretation.
The entire universe is described
by a single wavefunction.
The wavefunction is assumed to
exist as the only reality from the
moment of the big bang.
Since there can be no observer or
observation that is separate from
the universe, the wavefunction
never collapses.
At any moment that “I” (as part of
the universe) make an
observation, the wavefunction
branches to manifest the world
that “I” observe with a probability
given by the wavefunction. There
is no wavefunction collapse, but
there is a manifestation of “my”
world.
Problems with the many-worlds
interpretation
• At the same moment that “my” observation manifests my
world, all of the other possibilities given by the
wavefunction are manifested as other worlds. There is a
“me” in every one of them.
• The different worlds cannot communicate with each
other.
• Since there is no wavefunction collapse, the
wavefunction of the universe continues forever.
• A world becomes manifest over all of its own space
simultaneously, thus, many-worlds is nonlocal.
• There is no explanation for how observation manifests
the different worlds.
A second daring prediction!
• Nobody will ever figure out how branching
occurs because it is assumed to start from
a wavefunction (which every physicist
knows is nothing but a mathematical
formula) and ends up with a physical
world!
Mark Everett (1963-), son of Hugh
Everett and founder of Eels
• “My father never, ever said anything to me about his
theories. I was in the same house with him for at least 18
years but he was a total stranger to me. He was in his
own parallel universe. He was a physical presence, like
the furniture, sitting there jotting down crazy notations at
the dining room table night after night. I think he was
deeply disappointed that he knew he was a genius but
the rest of the world didn’t know it.”
• Mark’s father, Hugh died of a heart attack at age 51. His
sister committed suicide at age 39 and his mother died
two years later. His cousin and her husband were flight
attendants who died in the Sept. 11, 2001 attacks.
Bell’s theorem
(John Stewart Bell, 1928-1990)
• Bell devised a way to
determine experimentally
whether reality could be
described by local, real
theories (i.e., local, hidden
variable theories) by
deriving an inequality that
was valid only if local, real
theories were valid.
• The inequality depended
only on experimentally
measured quantities, hence
it was independent of any
specific theory. Any
violation of the inequality
would prove that reality
cannot be both local and
real.
Many experiments have shown that
reality violates Bell’s inequality
• Thus, reality cannot be both local and real.
• Furthermore, using Bell’s inequality, Aspect, et
al. (1981-82) showed that reality is nonlocal.
• Then, Gröblacher, et al. (2007) showed that, if
hidden variables describes reality, reality must
be bizarre and counterintuitive.
• However, even before these experiments had
been done, physicists had largely abandoned
the assumption of real particles. Thus, they had
abandoned the assumption that particles exist if
they are not observed.
A purely subjective interpretation of
quantum theory
• Currently, the only possible purely subjective
interpretation is the instrumentalist interpretation,
which states that quantum theory correctly predicts
the probability that an observation will yield a specific
result (e.g., the probability that a position
measurement will yield a specific position).
• This is purely subjective if there is no objective
wavefunction and both the prediction and the
observation are subjective.
• If it is purely subjective, there are no problems of
collapse, branching, and nonlocality because they all
result from the assumption that the wavefunction is
objective.
A third daring prediction!
• Both the Copenhagen and many-worlds
interpretations will eventually either be
abandoned or will be made purely
subjective by assuming that the
wavefunction is a tool for calculating
probabilities, instead of being objectively
real.
The experiments of Benjamin Libet,
et al. (1973)
• Subject is told to lift a finger whenever he/she
chooses.
• The EEG of subject is measured simultaneously
with the EMG from the finger.
The results
•
•
•
•
The subject associates his/her awareness of the urge to act with his/her
observations of the time on a clock. No separate muscle action is required.
This process is repeated many thousands of times and the results are
averaged.
Result: The average EEG signal begins 0.3 s before the subjective
awareness of an impulse to lift the finger.
Thus: The brain begins to process a muscle act prior to the subjective
awareness of the urge to act!
The experiments of Soon, Brass,
Heinze, and Haynes (2008)
• Functional MRI (blood oxygen level dependent) measurements of
the brain showed that the brain begins to process pushing either the
left button (dark voxels) or the right button (light voxels) up to 10 s
before any awareness of the subjective urge to push a button.
• Instead of watching a clock, the subject watched letters being
flashed on a screen every 0.5 s in random order. The randomness
guaranteed that the subject could not anticipate the letters.
Generalization of these
experiments
• Any mental or sensory event (as measured by
brain waves or scans) happens before “our”
awareness of it (as measured by subjective
response) because the brain requires time to
process the event before we can become aware
of it .
• Thus, all subjective experiences happen after
the corresponding objective events. This
applies to “volitional” experiences as well as
“nonvolitional” ones.
Example: Free will
• Free will assumes that we can choose our
thoughts.
• If we can choose our thoughts, why do we have
thoughts that we don’t want?
• Free will assumes that we can choose our
feelings.
• If we can choose our feelings, why do we have
feelings that we don’t want?
• Free will assumes that we can choose our
actions.
• If we can choose our actions, why do we do
things that we don’t want to do?
Exercises on free will
• To choose means to have control over choice.
• Try to stop thinking for 30 seconds. Were you
successful?
• Try to stop feeling for 30 seconds. Were you
successful?
• Try to stop sensing for 30 seconds. Were you
successful?
• Try to stop all muscle action for 30 seconds.
Were you successful?
• If “we” can’t control our thoughts, feelings,
sensations, and actions, what can “we” control?
Can “we” control anything?
• “We” experience thoughts, feelings,
emotions, sensations, and actions but
“we” can see directly that “we” cannot
control them.
• “We” experience will but “we” can see
directly that it is not free.
If “we” think “we” have free will but
don’t…
• …”we” will think “we” can control “our”
thoughts and actions, but will actually not
be able to.
• If “we” think “we” should have different
thoughts, feelings, emotions, sensations,
actions, and “we” think “we” should be
able to fix them, “we” will find out that “we”
cannot.
• Then “we” will suffer.
The cause of suffering
• Suffering is a result of identification with a “me”.
• Identification with a “me” results in the belief that “we”
can do things and control things.
• The belief that “we” can do and control results in our
judging, clinging, and resisting.
• “We” cling to the notion that we can do something, and
resist the notion that “we” cannot.
• “We” judge our thoughts, feelings, emotions, sensations,
and actions to be good/bad, right/wrong, virtuous/evil,
etc., and…
• …“we” cling to the “good” ones and resist the “bad”
ones.
• It is judging, clinging, and resisting that comprise
suffering, not the thoughts, feelings, emotions,
sensations, and actions in themselves.
Examples of judging, resisting, and
clinging
• “I” should not have these thoughts (“I”
should have only pure thoughts).
• “I” should not have these feelings (“I” should
have only pleasant feelings).
• “I” should not have these emotions (“I”
should have only loving emotions).
• “I” should not have these sensations (“I”
should have only pleasant sensations).
• “I” should not act the way “I” do (“I” should
always act compassionately).
If “we” really do have control, why is
clinging to it necessary?
• Perhaps “we” cling to the idea of having
control because “we” are afraid not to.
• In fact, at some level, perhaps “we” know
that “we” have no control but are afraid to
know it!
• But, is control necessary?
• Perhaps “we” would be just fine without it!
The end of suffering
• “We” investigate the “me” that thinks it can
choose or do.
• When “we” do so, “we” are not be able to
find it.
• When “we” see clearly that there is no
“me”, suffering ends.
• This might have to be repeated many
times.
Nonduality
• Nonduality is the teaching that all there is is
Consciousness and Consciousness is all there
is.
• Symbolically, Consciousness is both the circle
(Awareness) and everything inside it (arisings in
Awareness).
Duality
• Consciousness is always
whole and unsplit.
• However, Consciousness
seems to be split into
separate parts with
names (e.g., yin and
yang).
• Anything that is
thought to be separate
from anything else is
nothing but a concept.
• For example, yin and
yang are nothing but
concepts.
YANG
YIN
YIN
The basic split
• Consciousness seems to be split into “I”/“me”
and not-”I”/”me”.
• However, nondualistically, there is no separate
“I”…
• …and there is no “you” that is separate from
"me".
• “You” and “I” are only concepts in Awareness.
• However, the illusion of separation is extremely
persistent.
• All spiritual practice has the aim of seeing
through it.
• Clearly seeing through this illusion is called
“disidentification, “enlightenment”, “awakening”,
or “nirvana”.
If I am not a concept, what am
I?
• Nondualistically, I am pure Awareness
without any separation from anything.
• I am the circle, the yin, and the yang.
• That is my true nature…
• …and I have never been anything
else.
Spiritual practice
• Spiritual practice helps us to see that I am
not separate from anything else.
• It helps us see that there is no “I” that is
separate, or that can do anything or
control anything.
• The paradox of spiritual practice: We have
to do it in order to see that we are not
doing it!
• There are many spiritual practices, almost
as many as there are teachers.
Inquiry: The most common spiritual
practice in the teaching
of nonduality
• There are two basic kinds of inquiry:
− self-inquiry (lower case), and…
− Self-inquiry (upper case).
self-inquiry (lower case)
self-inquiry is the investigation of the “I”:
– Ask: Who/what is it that is thinking this?
Then, try to find the thinker.
– Ask: Who/what is it that is feeling this?
Then, try to find the feeler.
– Ask: Who/what is it that is sensing this?
Then, try to find the senser.
– Ask: Who/what is it that is doing this?
Then, try to find the doer.
What do you find?
• If you find a thinker, feeler, senser, or
doer, who/what is it that finds it?
• Which is you?
• If you don’t find a thinker, feeler,
senser, or doer, can there be one?
• Then, what are you?
Self-inquiry (upper case)
• Self-inquiry is the investigation of the true
I.
– Ask: What is it that is aware? Then try to
find it.
– If you find it, what is it that finds it?
(Anything that can be found cannot be
what finds it.)
– If you can’t find it, but you know that you
are aware, what are you?
Namaste΄
“I as Awareness/Presence
acknowledge you as
Awareness/Presence.”