An Introduction to Probability and Inductive Logic

Propositions.

(a) Yes.

(b) I myself don't know if it is true, unless I trust the newspaper.

(c) Yes.

(d) Yes.

(e) Once again, I don't know if it is true, unless I trust the newspaper. There might be a big debate among snake scientists. Some suggest that the ball python was not named after its tendency to curl up into a ball. Instead, it was named after the famous explorer and snake expert, Emily Ball. The question may never be settled. We may never be really sure why this snake is called a ball python. We may not know whether what the paper wrote is true, or whether it is false. But we know it is true-or-false.

(f) Yes.

(g) No. The snakes may be attractive to Joe, but probably some other people think the snakes are repulsive or scary. This statement is not what logicians call a proposition, because it expresses an attitude more than a matter of fact.

(h) Yes. This is a proposition about what Joe feels or thinks.

(i) No. It is not even a sentence. Hence it does not express a proposition.

(j) No. The slang expression “I'm not really too thrilled” is more a way of expressing an attitude than stating a fact, so we will not count this as a proposition.

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