 | WILLIAM T HARRIS - 1884 - 482 pages
...negation ; and, of course, what is true of triangle is true of all general ideas ; they are negations. The sum of the three angles of a triangle is equal to two right angles. This is a proposition to be demonstrated. I draw a triangle, and prove that the three angles... | |
 | Euclid, John Casey - Euclid's Elements - 1885 - 340 pages
...Projectives, page 52. HOTE B. LEGENDRE'S AND HAMILTON'S PROOFS or EUCLID, i. xxxn. The discovery of the Proposition that "the sum of the three angles of a triangle is equal to two right angles ' ' is attributed to Pythagoras. Until modern times no proof of it, independent of the theory... | |
 | Euclides - 1885 - 340 pages
...Projectives, page 82. NOTE B. LEGENDRE'S AND HAMILTON'S PROOFS OF EUCLID, i. xxxii. The discovery of the Proposition that "the sum of the three angles of a triangle is equal to two right angles" is attributed to Pythagoras. Until modern times no proof of it, independent of the theory of... | |
 | Antonio Rosmini-Serbati - 1885 - 668 pages
...mathematical affirmations — for example, "The consequence is contained in the principle," or " The sum of the three angles of a triangle is equal to two right angles " — then the copulative is signifies only ideal being. If the affirmation descends to the... | |
 | Education - 1888 - 634 pages
...etc., €tc., and that we shall one day die. On this hypothesis all general knowledge, such as " the sum of the three angles of a triangle is equal to two right angles," is impossible, for this statement transcends the experience of any individual. The second... | |
 | Antonio Rosmini - Psychology - 1886 - 660 pages
...mathematical affirmations — for example, "The consequence is contained in the principle," or " The sura of the three angles of a triangle is equal to two right angles " — then the copulative is signifies only ideal being. If the affirmation descends to the... | |
 | Gabriel Compayré - Education - 1887 - 516 pages
...mentioned above ; but it should be recollected that no "System of mere measurements can ever prove that the sum of the three angles of a triangle is equal to two right angles. (P.) 421. ARE THERE OBJECT-LESSONS IN ARITHMETIC AND GEOMETRY ? — We do not think that there... | |
 | Education - 1887 - 720 pages
...equal. 19-21. What is an isoscles triangle '( an equilateral triangle ; a scalene triangle f 22-24 Prove that the sum of the three angles of a triangle is equal to two right angles. 26-27. Name three ways in which triangles may be proved equal. 28-30. Prove that in a triangle... | |
 | Joseph Baldwin - Educational psychology - 1887 - 332 pages
...phenomena. 2. Mental Phenomena. — I perceive the beautiful lily, I remember the cheering song. I discern that the sum of the three angles of a triangle is equal to two right angles. I grieve over the loved and lost. I determine to study psychology. I perceive myself remembering,... | |
 | Joseph Baldwin - 1887 - 360 pages
...angles ; but this triangle represents all triangles ; therefore we infer the general truth — the sum of the three angles of a triangle is equal to two right angles. 3. Self, as reason, verifies his conclusions. By analysis we reduce our arguments to judgments,... | |
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After remarking that the mathematician positively knows that the sum of the three angles of a triangle is equal to two right angles... 
