【Alfred Tarski / Introduction to Logic / Translated into English by Olaf Helmer】
It would be funny if I sent this to someone online, who says what he says is logically good:
--Therefore, a man using the word "or" in the meaning of contemporary logic will consider the expression given above:
2 • 2 = 5 or New York is a large city
as a meaningful and even a true sentence, since its second part is surely true. (P23, II, 7)
Or even his take on "if 2 • 2 = 5, then New York is a large city" being true (P26, II, 8) because 2 • 2 = 5 is a hypothesis and New York's size is a true conclusion.
--...whenever, in a sentence, we wish to say something about a certain thing, we have to use, in this sentence, not the thing itself but its name or designation. (P58, III, 18)
However, we never should confuse this fallibility of daily logic with science (another mistake of the science person I mentioned).
--Strictly speaking, the terms "sentential function" and "designatory function" do not belong to the domain of logic or mathematics. (P102, V, 32)
And if they uttered the word "model," we can assert that models are not exactly the essence itself, but a realization of certain logic (P126, VI, 38) - which is so often overlooked when we are talking about models in social sciences and humanities - or if they started quoting Gödel, we can ask if they are aware of incompleteness being "two relevant contradictory sentences of which neither can be proved in that discipline" (P135, VI, 41)
However, this book has some deficits: it's not really idealistic as a textbook for "everyone" it calls itself to be: it doesn't have answers for its exercises, its explanations of sufficient verbal explanations about procedures of each proofs (unlike Russell's introductory works). Overall, I'd recommend it if you don't consider it a textbook, but as a test book itself to check on one's own deductive thinking.