Fourth Edition, 1920.
§ 1. Logic is the science that explains what conditions must be fulfilled in order that a proposition may be proved, if it admits of proof. Not, indeed, every such proposition; for as to those that declare the equality or inequality of numbers or other magnitudes, to explain the conditions of their proof belongs to Mathematics: they are said to be quantitative. But as to all other propositions, called qualitative, like most of those that we meet with in conversation, in literature, in politics, and even in sciences so far as they are not treated mathematically (say, Botany and Psychology); propositions that merely tell us that something happens (as that salt dissolves in water), or that something has a certain property (as that ice is cold): as to these, it belongs to Logic to show how we may judge whether they are true, or false, or doubtful. When propositions are expressed with the universality and definiteness that be
Cara Devon has always suffered curiosity and im... Read more
When the economic downturn ends Matty Cruz’s co... Read more
A telekinetic teenager. A telepathic child. A p... Read more
A century after an apocalyptic war reduces all... Read more
The list of books below is based on the weekly downloads by our users regardless of eReader device or file format.
See more popular titles from this genre.