I won’t be going through the entire work trying to summarize it all. Nothing that all-encompassing. I’m just going to quote some passages I found interesting, sometimes commenting on them, sometimes not. I’ll also include questions that the text brought to mind that maybe some people will have ideas about. I’m hoping to get a good grasp of what Ayer was saying. I’ll appreciate any help anyone can provide.
Chapter titles in this book:
- Ch. I. The Elimination of Metaphysics
- Ch. II. The Function of Philosophy
- Ch. III. The Nature of Philosophical Analysis
- Ch. IV. The A Priori
- Ch. V. Truth and Probability
- Ch. VI. Critique of Ethics and Theology
- Ch. VII. The Self and the Common World
- Ch. VIII. Solutions of Outstanding Philosophical Disputes
A quote from Ch. I, pg. 37:
It seems to me that if we adopt conclusive verifiability as our criterion of significance, as some positivists have proposed, our argument will prove too much. Consider, for example, the case of general propositions of law–such propositions, namely, as “arsenic is poisonous”; “all men are mortal”; “a body tends to expand when heated.” It is of the very nature of these propositions that their truth cannot be established with certainty by any finite series of observations.
This didn’t seem correct at first. I was thinking that you can test the effects of arsenic and verify that it is poisonous. The same is true with the expansion of a body when heated. Then I thought about the middle statement, “all men are mortal.” You can’t really verify this.There could be a long term study done using a random group of people. If they all die at some point, then the statistical probability that all people die is high, but it doesn't prove that all people will die.
After getting to this point, I thought again about the other two statements. Arsenic is poisonous to some organisms but no doubt it is not always poisonous to all organisms in all situations, and any study that could be done could not cover all organisms or all situations, so you can only make a tentative, statistically-based claim. The same is true of the third statement since possibly not all bodies expand when heated and you could only say that this is always true if you tested all bodies, an impossible task.
So I thought it through and made it to Ayer's position.