How Bertrand Russell answers: Does matter really exist? How can we know?
- What we need to know: -
• Sense-data: things that are immediately known in sensation
• Sensation: the experience of being aware of sense-data
• Physical object: an object that exists
• Matter: all objects that exist
• Many philosophers, say that nothing surely exists except for their own minds. These philosophers are called "idealists."
• How can they say that?
Idealists believe that matter is only "a collection of ideas" in our mind so it is easy to conclude that they do think that matter exists.
- What other philosophers say: -
- What Russell says: -
• Russell agrees with idealists that matter exists but differs in his reasoning.
While idealists believe that nothing is certain except for their minds and ideas, Russell argues that our thoughts, feelings, and sense-data should be thought of as certain too.
The mind is able to conceive input, sense-data, such as color and feel, but only momentarily such that the one mind interpreting one sense may be different than another mind interpreting another sense in a different moment. I can say that "the pen has a blue color" because something, the brain, is seeing the blue color, the sense-data. But if this same pen was shown to a different person wearing red colored spectacles, they might say "the pen has a purple color" because their brain is seeing the sense-data differently that it was seen moments before but the sense-data and brain still exist.
- What about the rest of matter? -
• If the idealists are right, an explanation of the source of sense-data could be that life is merely a dream; that everything a person sees and experiences are results of the mind in a dream mode.
• Russell argues a more simple reasoning method as to why matter exists is through common sense.
For example, while outside you see a bird walking on your left. You look to the right and see a tree. You look back to your left and see the bird is now flying with an worm in its mouth. You look back to the right and the tree has not appeared to change. You look back to the left and the bird is now unseen. Again, you look to your right but now you see the tree with the bird perched on a branch.
The bird was not a collection of your brain's ideas but rather it is an independent object that was able to move form one place to another without the requirement of your sense-data. The tree did not appear to move while you were looking but if it were only a collection of sense-data, the bird would have landed on nothing and by laws of gravity, fallen. Also, the bird picked up the worm out of hunger. But, if the bird was merely sense-data, how can the bird be hungry if our brain is the only thing capable of experiencing such feeling. Thus, it is common sense that matter exists independently of our brain and momentary sense-data.
- More on common sense: -
• The belief of common sense is a natural belief or an instinctive belief that comes about quickly when we reflect on experiences.
• Instinctive beliefs are organized and simplified as to not create confusion or absurdity. They are truly the source of our knowledge and without them, we have nothing.
• Philosophy struggles to organize the instinctive beliefs in a sort of hierarchy and Russell explains that there is still the possibility of fault in a belief. This fault, though, can only be assured by another belief that has yet to be proven false. In other words, an instinctive belief can only be wrong when it complicated the nature of matter.