A treatise on logic, or, The laws of pure thoughtSever & Francis, 1864 |
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Common terms and phrases
absolutely actually affirm the Consequent Affirmative already animal antecedent applied Aristotelic doctrine Aristotle assertion attributes Axiom called Cause class of things classification conceived Concept Conclusion connoted Consequent considered contained Contradictory Contraposition Conversion Copula Definition Demonstrative denote deny determined Disjunctive Disjunctive Syllogism distinct enounced Enthymeme equal event evidence Excluded exists explicated expressed Extension fact faculty Fallacy false Figure former Genus gism Hamilton Hence Immediate Inference individual Induction Inductive Reasoning infinite instance Intension Intuition knowledge language Laws of Thought Logic logicians Major Premise Marks Matter meaning ment merely Middle Term mind mode Modus tollens Moods nature necessary Negative not-X notion objects observed particular peculiar perception Predicate principle properly Proposition proved Pure Thought qualities Quantity rational reasoning reduced relation respect Rules sion Sir William Hamilton sophism Species Subalternation Subject sublating Sumption Syllogism tion tive true truth Universal valid whole words
Popular passages
Page 400 - Cause is the sum total of the Conditions, positive and negative, taken together ; the whole of the contingencies of every description, which, being realized, the consequent invariably follows.
Page 367 - As if we could not reason, and have knowledge about particulars: whereas, in truth, the matter rightly considered, the immediate object of all our reasoning and knowledge is nothing but particulars. Every man's reasoning and knowledge is only about the ideas existing in his own mind, which are truly, every one of them...
Page 392 - It consists in ascribing the character of general truths to all propositions which are true in every instance that we happen to know of.
Page 24 - And a little attention will discover that it is not necessary (even in the strictest reasonings) that significant names which stand for ideas should, every time they are used, excite in the understanding the ideas they are made to stand for : in reading and discoursing, names being for the most part used as letters are in Algebra...
Page 283 - He who calls you a man speaks truly: he who calls you a fool, calls you a man: therefore he who calls you a fool speaks truly.
Page 297 - Englishmen or not-Englishmen,' to the exclusion of the third possibility of a mixed force, so it is false to say, ' Every body must move in the place where it is, or in the place where it is not,' to the exclusion of the third possibility of moving partly in the one and partly in the other.
Page 337 - ... printing, gunpowder, and the magnet. For these three have changed the whole face and state of things throughout the world; the first in literature, the second in warfare, the third in navigation; whence have followed innumerable changes; insomuch that no empire, no sect, no star seems to have exerted greater power and influence in human affairs than these mechanical discoveries.
Page 175 - In as far as two notions (notions proper or individuals), either both agree, or one agreeing, the other does not, with a common third notion ; in so far, these notions do or do not agree with each other.
Page 305 - objections" against various parts of Scripture ; to some of which no satisfactory answer can be given ; and the incautious hearer is apt, while his attention is fixed on these, to forget that there are infinitely more, and stronger objections against the supposition that the Christian Religion is of human origin ; and that where we cannot answer all objections, we are bound in reason and in candour to adopt the hypothesis which labours under the least.
Page 265 - Axiom, as has been shown (page 54), 13 lirectly explicated into the two Laws, — 1. That to affirm the Reason or the Condition is also to affirm the Consequent ; and, 2. That to deny the Consequent is also to deny the Reason. A. ratione ad rationatum, a negatione rationati ad negationem rationis, valet consequentia. The single Premise affirming that this relation of Reason and Consequent exists between the Judgments which are its two parts, this Axiom compels us to infer immediately, or without...