“"The serious meaning of a concept," writes James, following Peirce, "lies in the concrete difference to some one which its being true will make. Strive to bring all debated conceptions to that "pragmatic" test, and you will escape vain wrangling. … If it can make no practical difference whether a given statement be true or false, then the statement has no real meaning."
If the method defined in this passage be accepted, and I can not see how any one can fail to accept it even if one prove unfaithful to it afterwards, then could anything more fully illustrate the meaning of the 'meaningless' than that hypothesis of other minds in which the analogy argument culminates? Whatever may be said for the reasoning, is its conclusion at least right? Alas, I can not know. If right, my experience cannot inform me if wrong, my experience cannot disillusion me. It makes no practical difference to me whether I am right or wrong. Pragmatic conclusion: I cannot have made a meaningful hypothesis.”

Part III : Selection on Education from Kant's other Writings, Ch. I Pedagogical Fragments, # 60
The Educational Theory of Immanuel Kant (1904)

Philosophy in the Twentieth Century (1982) p. 133.

Volume I, Book I http://books.google.com/books?id=US0bhPS4h2UC&pg=PA79
The World as Will and Representation (1819; 1844; 1859)

Kawaida and Questions of Life and Struggle (2008)

The Ethics of Belief (1877), The Weight Of Authority
Context: In regard, then, to the sacred tradition of humanity, we learn that it consists, not in propositions or statements which are to be accepted and believed on the authority of the tradition, but in questions rightly asked, in conceptions which enable us to ask further questions, and in methods of answering questions. The value of all these things depends on their being tested day by day. The very sacredness of the precious deposit imposes upon us the duty and the responsibility of testing it, of purifying and enlarging it to the utmost of our power. He who makes use of its results to stifle his own doubts, or to hamper the inquiry of others, is guilty of a sacrilege which centuries shall never be able to blot out. When the labours and questionings of honest and brave men shall have built up the fabric of known truth to a glory which we in this generation can neither hope for nor imagine, in that pure and holy temple he shall have no part nor lot, but his name and his works shall be cast out into the darkness of oblivion for ever.

1900s
Context: You ask that Mr. Taft shall "let the world know what his religious belief is." This is purely his own private concern; it is a matter between him and his Maker, a matter for his own conscience; and to require it to be made public under penalty of political discrimination is to negative the first principles of our Government, which guarantee complete religious liberty, and the right to each to act in religious affairs as his own conscience dictates. Mr. Taft never asked my advice in the matter, but if he had asked it, I should have emphatically advised him against thus stating publicly his religious belief. The demand for a statement of a candidate’s religious belief can have no meaning except that there may be discrimination for or against him because of that belief. Discrimination against the holder of one faith means retaliatory discrimination against men of other faiths. The inevitable result of entering upon such a practice would be an abandonment of our real freedom of conscience and a reversion to the dreadful conditions of religious dissension which in so many lands have proved fatal to true liberty, to true religion, and to all advance in civilization.

Letter to Mr. J.C. Martin concerning religion and politics (6 November 1908) http://www.theodore-roosevelt.com/images/research/txtspeeches/307.txt

Lecture II, "Circumscription of the Topic"
1900s, The Varieties of Religious Experience (1902)

Knowing Yourself: The True in the False (1996)