# Authors/Ockham/Summa Logicae/Book III-1

### From The Logic Museum

< Authors | Ockham | Summa Logicae

**PART III-1: OF THE SYLLOGISM**

## On the categorical syllogism

- Chapter 1 On the divisions and definitions of syllogisms.
- Chapter 2 Of certain preliminaries before we turn to the main subject.
- Chapter 3 On syllogisms of the first figure.
- Chapter 4 In which the claims of the previous chapter are proved.
- Chapter 5 For seeing when a syllogism is regulated by the
*dici de omni*and when not. - Chapter 6 On the sufficiency of the moods of the first figure
- Chapter 7 How the many arguments, which seem to contradict what was said above, are resolved.
- Chapter 8 That the major in the first figure can appropriately be singular and that the same conclusion follows as if it were universal.
- Chapter 9 On syllogisms from assertoric propositions taken in the oblique case.
- Chapter 10 On syllogisms in the second figure from propositions in the nominative case.
- Chapter 11 De reductione syllogismorum secundae figurae in quatuor modos primae figura
- Chapter 12 On syllogism [from propositions] in the oblique case in the second figure.
- Chapter 13 On how sometimes there is a good argument from affirmative propositions in the second figure.
- Chapter 14 On syllogisms of the third figure, and the sufficiency of their modes.
- Chapter 15 On syllogisms from propositions in the oblique case, in the third figure.
- Chapter 16 On expository syllogisms in the third figure.
- Chapter 17 On syllogisms from propositions in the past and future [tense] in the first figure.
- Chapter 18 On syllogisms from propositions in the past and future [tense] in the second figure.
- Chapter 19 On syllogisms from propositions in the past and future [tense] in the third figure.

## On modal syllogisms

- Chapter 20 On the uniform generation of syllogisms from
*de necessario*propositions in the first figure. - Chapter 21 On uniform syllogisms from
*de necessario*propositions in the second figure. - Chapter 22 On uniform syllogisms from
*de necessario*propositions in the third figure. - Chapter 23 On uniform syllogisms from
*de possibili*propositions in the first figure. - Chapter 24 On uniform syllogisms from
*de possibili*propositions in the second figure. - Chapter 25 On uniform syllogisms from
*de possibili*propositions in the third figure. - Chapter 26 On uniform syllogisms from
*de contingenti*(non necessary) propositions in the first figure. - Chapter 27 On uniform syllogisms from
*de contingenti*propositions in the second figure. - Chapter 28 On uniform syllogisms from
*de contingenti*propositions in the third figure. - Chapter 29 On uniform syllogisms from
*de impossibili*propositions - Chapter 30 How it is possible to syllogise from other modal propositions which are not usually called 'modal' in the sense above.

## On mixed syllogisms

### Necessary and assertoric

- Chapter 31 On the mixture of necessary and assertoric propositions in the first figure.
- Chapter 32 On the mixture of necessary and assertoric propositions in the second figure.
- Chapter 33 On the mixture of necessary and assertoric propositions in the first figure.

### Possible and assertoric

- Chapter 34 On the mixture of assertoric and possible propositions in the first figure.
- Chapter 35 On the mixture of assertoric and possible propositions in the second figure.
- Chapter 36 On the mixture of assertoric and possible propositions in the third figure.

### Contingent and assertoric

- Chapter 37 On the mixture of assertoric and contingent (non necessary) propositions in the first figure.
- Chapter 38 On the mixture of contingent and assertoric propositions in the second figure.
- Chapter 39 On the mixture of contingent and assertoric propositions in the third figure.

### Impossible and assertoric

- Chapter 40 On the mixture of assertoric and impossible propositions.

### Assertoric and other modal propositions

- Chapter 41 On the mixture of assertoric propositions, and other modal propositions modified by 'known', 'doubted', 'per se in the first mode', and so on in the first figure.
- Chapter 42 On the mixture of such modes and and assertoric propositions, in the second figure.
- Chapter 43 On the mixture of such modes and and assertoric propositions, in the third figure.

### Necessary and possible

- Chapter 44 On the mixture of necessary and possible propositions in the first figure.
- Chapter 45 On the mixture of necessary and possible propositions in the second figure.
- Chapter 46 On the mixture of necessary and possible propositions in the third figure.

### Necessary and contingent

- Chapter 47 On the mixture of necessary and contingent propositions in the first figure.
- Chapter 48 On the mixture of necessary and contingent propositions in the second figure.
- Chapter 49 On the mixture of necessary and contingent propositions in the third figure.

### Necessary and impossible

- Chapter 50 On the mixture of necessary and impossible propositions.

### De necessario and oher modals

- Chapter 51 On the mixture of
*de necessario*propositions and of other modes from those four in the first figure. - Chapter 52 On the mixture of
*de necessario*propositions and of other modals in the second figure. - Chapter 53 On the mixture of
*de necessario*propositions and of other modals in the third figure.

### Possible and contingent

- Chapter 54 On the mixture of possible and contingent in the first figure.
- Chapter 55 On the mixture of possible and contingent in the second figure.
- Chapter 56 On the mixture of possible and contingent in the third figure.

### Possible and impossible

- Chapter 57 On the mixture of possible and impossible in every figure.

### Possible and other modals

- Chapter 58 On the mixture of
*de possibili*propositions and of other modals in the first figure. - Chapter 59 On the mixture of
*de possibili*propositions and of other modals in the second figure. - Chapter 60 On the mixture of
*de possibili*propositions and of others in the third figure.

### Contingent and other modals

- Chapter 61 On the mixture of
*de contingenti*propositions and of other modals in the first figure. - Chapter 62 On the mixture of
*de contingenti*propositions and of other modals in the second figure. - Chapter 63 On the mixture of
*de contingenti*propositions and of other modals in the third figure.

## Other kinds of syllogism

- Chapter 64 On the mixture of other modal propositions than the previous four.
- Chapter 65 On syllogisms made from propositions having several exponents.
- Chapter 66 On syllogisms made from exclusives.
- Chapter 67 On syllogisms made from exceptives.
- Chapter 68 On hypothetical syllogisms.