Book, Paragraph

 1      I, 1 |          assertion of one of two contradictory statements (the demonstrator
 2      I, 15|         subject (for this is the contradictory of the assumption which
 3      I, 15|      impossibile establishes the contradictory which is opposed to this).
 4      I, 17|         the one statement is the contradictory of the other. But if this
 5      I, 23|       from the assumption of its contradictory; e.g. that the diagonal
 6     II, 8 | conclusion is converted into its contradictory or into its contrary. For
 7     II, 8 |          clear by the sequel. By contradictory opposition I mean the opposition
 8     II, 8 | conclusion is converted into its contradictory, the syllogisms will be
 9     II, 8 |           the syllogisms will be contradictory and not universal. For one
10     II, 8 | conclusion is converted into its contradictory, both premisses may be refuted,
11     II, 9 |        of the first, if into its contradictory, the contradictory. Let
12     II, 9 |      into its contradictory, the contradictory. Let A belong to all B and
13     II, 9 |         BC is converted into its contradictory, the premiss AB will be
14     II, 9 |           the premiss, AC by its contradictory. For if B belongs to some
15     II, 9 |         syllogism results in the contradictory of the minor premiss. A
16     II, 9 | conclusion is converted into its contradictory, both premisses can be refuted.
17     II, 9 | conclusion is converted into its contradictory, both premisses can be refuted.
18     II, 10| conclusion is converted into its contradictory, both premisses may be refuted
19     II, 10| conclusion is converted into its contradictory, both the premisses can
20     II, 10|        not refuted. But when the contradictory of the conclusion is assumed,
21     II, 10|       premiss, and when a result contradictory to the premiss, is obtained.
22     II, 11|   impossibile is proved when the contradictory of the conclusion stated
23     II, 11|      takes place not because the contradictory has been agreed to already,
24     II, 11|        supposition is false: its contradictory then is true. Similarly
25     II, 11|         then we must suppose the contradictory.~Again suppose that A belongs
26     II, 11|     refuted. Therefore it is the contradictory that we must suppose.~To
27     II, 11|         not the contrary but the contradictory ought to be supposed in
28     II, 11|   everything one or other of two contradictory statements holds good, then
29     II, 13|      proceed per impossibile the contradictory must be assumed. And it
30     II, 14|         of these, along with the contradictory of the original conclusion.
31     II, 14|         been taken, whenever the contradictory of the conclusion of the
32     II, 15|          is particular, they are contradictory.~We must recognize that
33     II, 15|      owed its contrariety to its contradictory premisses; if we assume
34     II, 20|  syllogism which establishes the contradictory. But if nothing is conceded,