In Theaetetus by Plato, Socrates discusses with young Theaetetus the matter
of knowledge. Socrates tries to help Theaetetus formulate a theory about what
knowledge is. For a moment, Theaetetus feels content with "... whatever
appears is to each one".
1
Russell introduces, in The Problems of Philosophy, the term
sense data to explain the above. Sense data is what appears to us through
perception, from our senses. What we see, hear, feel. If I have a quick look at
my bookshelf, it could be made out of wood. A closer look and feel reveals it's
laminated chipboard.
In Theaetetus, Plato writes about observing a
white object. It looks white to the eye.
But the object is not the
colour white, and an eye is not sight. Likewise Russell goes on adding
'sensation' as a term for the momentary experience of, for instance, the colour
white.
Russell means that we cannot
know what is real and questions the existence of matter and its nature. In The
Matrix (1999), the main character Neo discovers that the world everyone holds
for real is just computer code. It is a perception of the minds living in it,
but it is not real.
2
A proposition is a description of an object, that we are able to
share with others. It can be a statement either true or false.
Induced knowledge according to
Russell, is based on assumptions of things that we are habituated to through re-occurrence,
for instance the sun rising every day. Therefore they are held to be true, even
though they are merely assumptions.
Russell introduces knowledge
of general principles.
It can be summarized like
this:
If we understand that 2+2 = 4,
then we can also understand that 4+4 = 8 or that 2 apples + 2 apples = 4 apples.
When we realize something applies in general and not only for a particular
case, it can be considered knowledge of general principles.
Then there are logical
principles:
If yesterday was the 11th, I
believe that today is the 12th. Also, my calendar tells me that yesterday was
the 11th, so today must be the 12th. As Russell puts it "...
this 'implies' that, and that that 'follows from' this".
Statements
like these can be presumed to be always true and therefore of fact.
Russel writes: "The fundamental principle in the analysis of
propositions containing descriptions is this: Every proposition which we can understand
must be composed wholly of constituents with which we are acquainted." The
words in our descriptions must have a meaning to us, or else it would not be
comprehensible. Things that are not shareable with others, like unexpressed thoughts
or random grunts, are not propositions.
3
Knowledge by acquaintance can
be obtained by sense data, it is things that we are directly aware of. knowledge
by description can be a proposition given to us by someone else.
My attempt to understand Russell's
definition of descriptions:
A definite description describes a certain known object, like "the
X" or "X". The opposite is an ambiguous description which does
not specify an exact object, like "an X".
If an object is described as
'the X', there is only one object with a certain property. It's not known by
acquaintance. If 'the X exists', then there is only one instance of X.
If 'a is the X' an object has
the property X, and nothing else has.
4
"True belief" can be thought of as a
definition for knowledge. Some beliefs are wrong, Russell distinguishes erroneous
beliefs from true ones. He means that true belief is not knowledge when it is
deducted through false conclusions.
If I propose that the cold from the air outside transfers
to a warm room, if a window is opened, makes the room cold, then the conclusion
is correct. However it is based on false reasoning, since the second law of
thermodynamics states that heat flows from the warmer body to the colder and
not the other way around.
Russell means that explaining exactly how things are
with metaphysics is in vain, since arguments
can always be criticized and in the end unable to hold
ground.
Hegel describes how metaphysics can see the whole of
reality by only knowing a fraction of it. Russell goes on arguing that incomplete
ideas will lead to self-contradiction. Hegel means that we can iterate the idea,
until we find an 'Absolute Idea'. Russell criticizes this and finds it based on
uncertainties and assumptions.
Again the white object from Theaetetus:
We may know only that an object looks white to our
eye. Still we cannot conclude that the object is the colour white. Russell
writes "a truth about a thing is not
part of the thing itself, although it must, according to the above usage, be
part of the 'nature' of the thing".
Russell means philosophy can be used as criticism of
knowledge as long as it does not take on a destructive skeptical view, and
mentions the 'methodical doubt' by Descartes as a bad example.
Lastly he points out that philosophy may claim that it
helps us reduce the risk of making errors.
I find interesting that someone else thought about "The Matrix as example to explain Russell's sense-data theory.
SvaraRaderaIn particular I see many matches between this great movie and Plato's "Allegory of the cave".
Both Neo and Plato's prisoner live in a world of which representations are controlled by supervising agents, both perceive the images they are seeing are not the truth and manage to escape one following the path to the cave exit eventually enjoy the sunlight and the other choosing the "red pill" offered by Morpheus.
"This is your last chance. After this, there is no turning back. You take the blue pill - the story ends, you wake up in your bed and believe whatever you want to believe. You take the red pill - you stay in Wonderland and I show you how deep the rabbit-hole goes." - Morpheus, The Matrix, 1999
You say that Russell claims that philosophy could help us reduce the risk of making errors. I missed that in the book, but it is an interesting idea. I guess that if you translate that into your daily life; if you first consider why and how to do something then as a result your actions will be more well chosen. That off course does not stop you from making errors altogether, but they should be far less.
SvaraRaderaThat's right Jenny, in the end of chapter XIV. The limits of philosophical knowledge, Russell actually says that "Philosophy may claim justly that it diminishes the risk of error, and that in some cases it renders the risk so small as to be practically negligible." And then of course he also mentions that mistakes will be made, this is simply of our nature. And it's interesting, Russell criticizes Hegel in this book, and Hegel cites Kant, who wrote The critique of pure reason. A neat little work of 476 pages. I did read the few first pages of it and found some parts that I believe strengthens Russell's idea that metaphysics in a way, through criticism can aid us in the way we look at scientific methods:
SvaraRadera"Reason must approach nature with the view, indeed, of
receiving information from it, not, however, in the character of a pupil, who
listens to all that his master chooses to tell him, but in that of a judge, who
compels the witnesses to reply to those questions which he himself thinks fit
to propose." - Kant
Kant seems to believe that natural sciences for too long have been stuck in thinking in one way only, I suppose that which was in general thought to be "the right way".
But the philosophy might help us change our perspective. Kant also mentions how Copernicus changed perspective while trying to understand the celestial movements. Instead of imagining that the universe was revolving around the spectator, he imagined it the other way around. This part is used as an example of how the same thought or method could be applied to metaphysics.
Hi!
SvaraRaderaIt sure was an interesting comparison with The Matrix. You wrote how the world "is a perception of the minds living in it, but it is not real." This leads me to wonder what we even believe that reality consists of, or is supposed to consist of, if we are confident enough to state that our current world is not real. If it is not real, and we don't even know what "real" is, then how do we know that it is not real at all? Can we even know that, since just that requires us to have knowledge about the "realness" or reality, and as you know, many of us have been questioning ourselves during the last week what knowledge even is and whether it is able to exist. So..
By the way, what about the "mind"? Apparently, the mind is allowed to be real and exist, but not the world. Our sense-data is telling us that we have a mind, but it is likewise also telling us that there is a physical world out there.
We seem to be going in circles trying to make things clear for ourselves but we are only giving birth to yet more questions.
"What even is this?"..
Yes, what about our minds. George Berkeley believed in that material things do not exists but are only something that exists in our minds. This is nowadays called subjective idealism.
SvaraRaderaKant responds to Berkeley's idea his The Critique of Pure Reasoning by discussing how we
can think of, but not objectify Supreme Beings like God.
"there is no other way left than to make them subjective forms of our mode of intuition".
Kant is not so easy to interpret in five minutes, anyway, he also speaks of time and space not being actual physical objects and that we must regard them as being there and will always be there even though everything that is present within time and space will cease to exists.
I was looking for some evidence that a philosopher would clearly states that the we cannot even be sure our minds exists, however here I think I need to extend my hand and ask someone else out there, have you read such text by any author?