Appearance and reality
Russell questions the absolute character of knowledge and problem discernment in Philosophy.
What is the distinction between appearance and reality? Things that are known by perception are labeled sensory data. The collection of all physical objects is called matter.
Russell quotes the philosopher Berkeley, who said that objects do not exist outside of the senses. This I think is a disappointment. Objects exist independently of the senses and come within our reach if we are knowing or perceiving them.
Russell describes the appearance problem as philosophical. Is the reality of seeing a thing real? What about appearance when we get closer to its microscopic or macroscopic composition? For example: the size and heat of the sun increase as we get closer to it.
The existence of matter
The author introduces Descartes, who used to systematically doubt and, through his doubts, came to the conclusion: I think, therefore I am. Philosophically, it raises the question of whether objects exist outside of our senses. I would like to say yes: they do.
The nature of matter
Physical science has reduced all objects to movements. For example: light has waves and particles called waves.
Idealism
The first defender of idealism was Berkeley. According to him, everything exists in the mind. Here I think there is a misinterpretation of Berkeley’s thinking. We have to know or perceive and we do that with our senses.
The word Know is used in the sense of two things. First of all, it means the absence of error. The second aspect is the knowledge acquired by the senses. This is called knowing through knowledge. For knowledge by knowledge we come to know things by our senses. For example, when I see a table, I perceive that it is a table.
Russell is not clear about what he means by knowledge through description.
There is a knowledge of universals which are ideas like whiteness, brotherhood and justice, etc. Nouns and verbs according to Russell use descriptive content.
In induction
What is induction? Inductive knowledge proceeds from the general to the particular. A syllogism is an induction. For example: All men are mortal; Socrates is a man: therefore Socrates is mortal.
There are three laws of thought. The law of identity: what is: the law of contradiction: nothing can be and cannot be: the law of the excluded environment: everything must be and not be.
One of the historical controversies is between the empiricists and the rationalists. Empiricists hold that knowledge comes from experience. Is knowledge a priori or a posteriori that exists before the known or after the known?
Russell assumes that all mathematical knowledge is a priori. I would like to say that knowing the verifiability of mathematical truths is a posteriori.
The world of universals
The universals, ideas such as justice, truth, brotherhood exist in form or as ideas or are to put them into practice. Plato was wrong to assume that they exist in an ideal form.
