All 3 Uses of
right angle
in
Leviathan, by Thomas Hobbes
- For example, a man that hath no use of Speech at all, (such, as is born and remains perfectly deafe and dumb,) if he set before his eyes a triangle, and by it two right angles, (such as are the corners of a square figure,) he may by meditation compare and find, that the three angles of that triangle, are equall to those two right angles that stand by it.†
Chpt 1.4 *right angles = angles measuring 90 degrees (like the angle between a classroom floor and wall)
- For example, a man that hath no use of Speech at all, (such, as is born and remains perfectly deafe and dumb,) if he set before his eyes a triangle, and by it two right angles, (such as are the corners of a square figure,) he may by meditation compare and find, that the three angles of that triangle, are equall to those two right angles that stand by it.†
Chpt 1.4
- But he that hath the use of words, when he observes, that such equality was consequent, not to the length of the sides, nor to any other particular thing in his triangle; but onely to this, that the sides were straight, and the angles three; and that that was all, for which he named it a Triangle; will boldly conclude Universally, that such equality of angles is in all triangles whatsoever; and register his invention in these generall termes, Every Triangle Hath Its Three Angles Equall To Two Right Angles.†
Chpt 1.4
Definition:
an angle measuring 90 degrees (like the angle between a classroom floor and wall)