Further clarification to be given later.

Further clarification to be given later. The logical positivists describe a proposition as 'meaningful' if its truth or falsity can be affirmed within the limits of sense experience. This is equal to saying, "The content of metaphysical propositions lies beyond sense experience". With this, the positivists assert an indisputable truth, that the subjects of metaphysics are not empirical something which the rationalists have stressed all along.

What would the positivist say about such propositions as relate to nature but cannot be verified by sense experience, such as a statement about the existence of mountains and valleys on the other side of the moon? Positivism revises its original position to assert that that which is important here is logical possibility, not actual possibility.

However, the notion of logical possibility is a metaphysical notion, and thus positivism, in the last analysis, has to adopt a metaphysical criterion of 'meaning'. Metaphysical propositions are as meaningful as any other, in that they relate to realities independent of the mind and the logical possibility of being true or false holds in their case. Previous…