Part III, Chapter 19: Of the different Ways of Reasoning ill, which are called Sophisms (third part)
Judging of a thing by that which only belongs to it accidentally.
This sophism is called in the schools fallacia accidentis, which is, when we draw a simple, unrestricted, and absolute conclusion, from what is true only by accident. This is done by the number of people who decry antimony, because, being misapplied, it produces bad effects; and by others, who attribute to eloquence all the bad effects which it produces when abused, or to medicine the faults of certain ignorant doctors.
It is in this way that the heretics of the present day have led so many deluded people to believe that we ought to reject, as the inventions of Satan, the invocation of saints, the veneration of relics, the prayer for the dead, because somewhat of abuse and superstition had crept in amongst these holy practices, authorised by all antiquity; as though the bad use which men may make of the best things rendered them bad.
We often fall into this vicious reasoning when we take simple occasions for true causes. As if any should accuse the Christian religion of having been the cause of the murder of an infinite number of persons, who have chosen rather to suffer death than to renounce Jesus Christ; whereas it is to neither the Christian religion, nor the constancy of the martyrs, that these murders ought to be attributed, but simply to the injustice and cruelty of the pagans. It is through this sophism, also, that good people are often said to be the cause of all the evils which they might have avoided by doing things which would have offended their conscience; because, if they had chosen to relax in that strict observance of the law of God, these evils would not have happened.
We see also a famous example of this sophism in the ridiculous reasoning of the Epicureans, who concluded that the gods must have a human form, because among all creatures in the world men alone had the use of reason. The gods, said they, are very happy; none can be happy without virtue; there is no virtue without reason; and reason is found nowhere except in the human form; it must be avowed, therefore, that the gods have the human form. But they were very blind, not to see that although in men the substance which thinks and reasons be united to a human body, it is, nevertheless, not the human figure which enables men to think and reason,—it being absurd to imagine that reason and thought depend on anything which is in a nose, a mouth, cheeks, two arms, two hands, two feet; and it was thus a puerile sophism in these philosophers to conclude that reason could only dwell in the human form, because in man it is accidentally united with that form.
Passing from a divided sense to a connected sense, or from a connected sense to a divided sense.
The former of these sophisms is called fallacia compositionis; the latter, fallacia divisionis. They will be understood better by examples.
Jesus Christ says, in the gospel, in speaking of his miracles, The blind see, the lame walk, the deaf hear. This cannot be true if we take these things separately, and not together, that is to say, in a divided, and not in a connected sense. For the blind could not see, remaining blind; and the deaf could not hear, remaining deaf;—but those who had been blind before were so no longer, but now saw; and so of the deaf.
It is in the same sense, also, that God is said, in the Scripture, to justify the ungodly. For this does not mean, that he considers as just those who are still ungodly, but that he renders just, by his grace, those who before were ungodly.
There are, on the contrary, propositions which are true only in an opposite sense to the divided sense: as when St Paul says, that liars, fornicators, and covetous men shall not enter into the kingdom of heaven. For this does not mean that none of those who have had these vices shall be saved, but only that those who have continued addicted to them, and have never left them by turning to God, shall have no place in the kingdom of heaven.
It is easy to see that we cannot, without a sophism, pass from one of these senses to the other; and that those, for example, would reason ill, who should promise themselves heaven while remaining in their sins, because Jesus came to save sinners, and because it is said in the gospel that women of evil life shall enter into the kingdom of God before the Pharisees; or who, on the other hand, having forsaken evil, should despair of their salvation, as having nothing to expect but the punishment of their sins, because it is said that the anger of God is reserved against all those who live ungodly lives, and that none who are vicious shall have any part in the inheritance of Jesus Christ. The first would pass from the divided sense to the compounded, in promising themselves, though still continuing sinners, that which is only promised to those who cease to be so, by true conversion; and the last would pass from the compounded sense to the divided, in applying to those who have been sinners, but who cease to be so by turning to God, that which refers only to sinners remaining in their sins and wicked life.
Passing from what is true in some respect, to what is true absolutely.
This is what is called in the schools a dicto secundum quid ad dictum simpliciter. The following are examples: The Epicureans proved, again, that the gods must have the human form because it is the most beautiful, and every thing which is beautiful must be in God. This was bad reasoning; for the human form is not beautiful absolutely, but only in relation to bodies. And thus, the perfection being only in some respect, and not absolutely, it did not follow that it must be in God because all perfections are in God, it being only those which are perfections absolutely, that is to say, which contain no imperfection, which were necessary in God.
We find also in Cicero, in the Third Book, of the nature of the gods, an absurd argument of Cotta against the existence of God, which may be referred to the same vice. How, says he, can we conceive God. since we can attribute no virtue to him? For shall we say that he has prudence? But since prudence consists in the choice between good and evil, what need can God have for this choice, not being capable of any evil? Shall we say that he has intelligence and reason? But reason and intelligence serve to discover to us that which is unknown from that which is known; now, there can be nothing unknown to God. Neither can justice be in God, because this relates only to the intercourse of men; nor temperance, since he has no desires to moderate; nor strength, since he is susceptible of neither pain nor labour, and is not exposed to any danger. How, therefore, can that be a god which has neither intelligence nor virtue?
It is difficult to conceive anything more impertinent than this method of reasoning. It resembles the notion of a rustic who, having never seen houses covered with any thing but thatch, and having heard that there were in towns no roofs of thatch, should conclude therefrom that there were no houses in towns, and that those who dwell there are very miserable, being exposed to all the inclemencies of the weather. This is how Cotta, or rather, Cicero, reasons. There can be no virtues in God like those in men; therefore, there is no virtue in God. And what is so marvellous is, that he concludes that there is no virtue in God, only because the imperfection which is found in human virtue cannot be in God; so that what proves to him that God has no intelligence, is the fact that nothing is hid from him, that is to say, that he sees nothing because he sees everything; that he can do nothing, because he can do everything; that he enjoys no happiness, because he possesses all happiness.
Abusing the ambiguity of words, which may be done in different ways.
We may reduce to this kind of sophism all those syllogisms which are vicious, though having four terms, whether this be because the middle is taken twice particularly, or because it is taken in one sense in the first proposition, and in another in the second, or, finally, because the terms of the conclusion are not taken in the same sense in the premises as in the conclusion: For we do not restrict the word ambiguity to those words alone that are manifestly equivocal, which scarcely ever mislead any one, but we comprise under it anything which may change the meaning of a word, especially when men do not easily perceive that change, because different things being signified by the same word, they take them for the same thing. On this subject, we may refer to what has been said towards the end of the First Part, where we have also spoken of the remedy which should be employed against the confusion of ambiguous words by defining them so precisely that none can be deceived.
We shall content ourselves, therefore, with referring to some examples of this ambiguity, which sometimes deceive men of ability, such as those which we often find in words which signify some whole, which may be taken either collectively, for all their parts together, or distributively, for each of these parts.
In this way is to be resolved that sophism of the stoics, who concluded that the world was an animal endowed with reason, because that which has the use of reason is better than that which has not. " Now there is nothing,” say they. '’ which is better than the world, therefore, the world has the use of reason.” The minor of this argument is false, since it attributes to the world that which belongs only to God, which is, that of being such that it is impossible to conceive anything better, or more perfect. But in limiting ourselves to creatures, although we may say that there is nothing better than the world, taking it, collectively, for the totality of all the beings that God has created, all that we can conclude from this at most is, that the world has the use of reason in relation to some of its parts, such as are angels and men, and not that the whole together was an animal endowed with the use of reason. This would be the same kind of bad reasoning as to say—man thinks; now, man is composed of mind and body; therefore, mind and body think. For it is enough, in order that we may attribute thought to the whole man, that he thinks in relation to one of the parts; and from this it does not at all follow that he thinks in the other.
Deriving a general conclusion from a defective induction.
When, from the examination of many particular things, we rise to the knowledge of a general truth—this is called induction. Thus, when we find, by the examination of many seas, that the water in them is salt, and of many rivers, that the water in them is fresh, we infer, generally, that the water of the sea is salt, and that of rivers fresh. The different experiments by which we have found that gold does not diminish in the fire, leads us to judge that this is true of all gold. And since no people have ever been found who do not speak, we believe confidently that all men speak, that is to say, employ sounds to express their thoughts. It is in this way that all our knowledge begins, since individual things present themselves to us before universals, although, afterwards, the universals help us to know the individual.
It is, however, nevertheless true, that induction alone is never a certain means of acquiring perfect knowledge, as we shall show in another place. The consideration of individual things furnishes to our mind only the occasion of turning its attention to its natural ideas, according to which it judges of the truth of things in general. For it is true, for example, that I might never perhaps have been led to consider the nature of a triangle if I had not seen a triangle, which furnished me with the occasion of thinking of it. But it, nevertheless, is not the particular examination of all the triangles which makes me conclude generally and certainly of all, that the space which they contain is equal to that of the rectangle of their whole base and a part of their side (for this examination would be impossible), but simply the consideration of what is contained in the idea of a triangle which I find in my mind.
Be this as it may, reserving the consideration of this subject for another place, it is enough to say here, that defective inductions, those, that is to say, which are not complete, often lead us to fall into error; and I shall content myself with referring to one remarkable example of this.
All philosophers had believed, up to the present time, as an undoubted truth, that a syringe being well stopped, it would be impossible to draw out the piston without bursting it, and that we might make water rise as high as we chose in pumps by suction. What made this to be so firmly believed was, that it was supposed to have been verified by a most certain induction derived from a multitude of experiments; but, both are found to be false, since new experiments have been made which have proved that the piston of a syringe, however well it may be stopped, may be drawn out, provided we employ a force equal to the weight of a column of water of more than 23 feet in height, of the diameter of the syringe; and that we cannot raise water, by suction in a pump, higher than 22 or 23 feet