Authors/Ockham/Summa Logicae/Book III-3/Chapter 31

Latin	English
[CAP. 31. DE SPECIE ARGUMENTI QUAE DICITUR INDUCTIO]	[Chapter 31. On the species of argument called 'induction']
Circa inductionem, quae ponitur una species argumenti sive consequentiae, est primo sciendum quid est inductio. Et est sciendum quod "inductio est a singularibus ad universale progressio". Ad hoc autem quod fiat inductio requiritur quod tam in singularibus ƿ quam in universalibus sit idem praedicatum et solum sit variatio a parte subiectorum.	On induction, which is given as a species of argument or consequence, it should first be known what it is.  And it should be known that "induction is a progression from singulars to the universal".  But for induction to come about it is required that there is the same predicate in both the singulars and the universals, and that the only variation is on the side of the subject.
Potest autem tripliciter fieri variatio a parte subiectorum: uno modo, ponendo praecise pronomen demonstrativum in singularibus a parte subiecti, sic arguendo: iste currit et ille currit, et sic de singulis, igitur omnis homo currit. Aliter fit variatio, ponendo a parte subiecti pronomen demonstrativum cum subiecto propositionis universalis, sic arguendo: hoc album currit et illud album currit, et sic de singulis, igitur omne album currit. Aliter fit variatio, ponendo nomina propria in singularibus pro subiectis, si nomina sint imposita, sic arguendo: Sortes currit, Plato currit, et sic de singulis, igitur omnis homo currit.	For there can be three kinds of variation on the side of the subject.  In one way, by giving precisely a demonstrative pronoun in the singulars on the side of the subject, in arguing "this one runs, and that one, and so on for the singulars, therefore every man runs".  In a second way, by giving a demonstrative pronoun on the side of the subject with the subject of a universal proposition, thus "thus white thing runs, and that white thing runs, and so on for the singulars, therefore every white thing runs".  In a third way, by giving proper names in the singulars as subjects, if names are imposed, thus "Socrates runs, Plato runs, and so on for the singulars, therefore every man runs".