The Principles of Logic: For High Schools and Colleges |
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affirmative conclusion antecedent Arguments in Figure Assumptions attributes Cæsar categorical Classification clusion coextensive comprehension consequent contained contrary converse converted simply coördinate Definition denotes Denying the antecedent Disjunctive Syllogisms distribute the predicate division Enthymeme Euathlus excluded expression extensive quantity extreme fallacy false finite Formal Fallacies free agent Hamilton harmony of thought Hence highest genus Hypothetical Syllogisms illicit process implies the falsity implies the truth infer intersects invalid involves judgment Law of Contradictories laws of thought logical major premise major term Mathematical Induction middle term minor term moon moral nature non-P is Q non-S objects order to distribute Particular premises phenomena polygon Prem premise is universal proposition prove Real induction reason reductio ad absurdum relation responsible agent space is infinite species subject and predicate subordinate thing tion tive triangles undistributed middle universal negative valid moods whole
Popular passages
Page 145 - To make the comprehensibility of a datum of consciousness the criterion of its truth would be, indeed, the climax of absurdity. For the primary data of consciousness as themselves the conditions under which all else is comprehended, are necessarily themselves incomprehensible. We know, and can know only, that they are, not how they can be.
Page 110 - What belongs (or does not belong) to the containing whole, belongs (or does not belong) to each and all of the contained parts. The latter by the rule — What belongs (or does not belong) to all the constituent parts, belongs (or does not belong) to the constituted whole.
Page 149 - All men are mortal: that the general principle, instead of being given as evidence of the particular case cannot itself be taken for true without exception, until every shadow of doubt which could affect any case comprised with it, is dispelled by evidence aliunde; and then what remains for the syllogism to prove?
Page 46 - In this case, the concept, responsible agent, is contained under the concept, free agent; that is, the class of responsible agents is a species of which the class of free agents is the genus. The concept, man, is contained under the concept, responsible agent ; that is, the class, man, is a species of which the class of responsible agents is the genus. Hence, on the principle, that a part of a part is a part of the whole, the concept, man, is contained under the concept free agent.
Page 144 - Taking it as a whole: space, it is evident, must either be limited, that is, have an end, and circumference; or unlimited, that is, have no end, no circumference. These are contradictory suppositions; both, therefore, cannot, but one must, be true. Now let us try positively to comprehend, positively to conceive,* the possibility of either of these two mutually exclusive alternatives. Can we represent, or realize in thought, extension as absolutely limited? in other words, can we mentally hedge round...
Page 149 - ... any case comprised within it is dispelled by evidence aliunde" it is a fact that the general principle, though not of course true unless every particular case included under it is true, is itself often established, in its utmost generality, without any reference to the particular cases involved. Do we establish the general principle that, Any term of an Arithmetical Progression is equal to the first term plus the number of the term minus one into the common difference, by examining all of the...
Page 144 - Taking it as a whole : space, it is evident, must either be limited, that is, have an end, and circumference ; or unlimited, that is, have no end, no circumference. These are contradictory suppositions ; both, therefore, cannot, but one must, be true. Now, let us try positively...
Page 51 - Let us now take an argument with an undistributed middle : All P is M. All S is M. .-. All S is P. The conclusion does not necessarily follow from the premises, though it may be accidentally true, as seen in the second diagram above. Let now the major premise be a case of coextension, then M will be distributed and the argument valid. All P is M. All S is M. .-. All S is P. "We frequently meet with such reasonings in scientific works.
Page 121 - A MIRACLE is an effect or event, contrary to the established constitution or course of things ; or, a sensible suspension or controlment of, or deviation from, the known laws of nature, wrought either by the immediate act, or by the...
Page 89 - That which has no composition of parts is indissoluble. That which is indissoluble is immortal. .-. The mind is immortal.