More on this book
Community
Kindle Notes & Highlights
Another trait of first principles—it follows from their being self-evident—is that they cannot be proven. This means that they are not conclusions that follow from premises; they are not truths dependent upon antecedent truths. This is because first principles represent truths that are absolutely fundamental. They are “first” in the strongest sense of the word.
Gray can exist as gray only because there are the distinct alternatives of black and white. That you might find yourself at times in a situation in which you see no clear alternatives does not mean, objectively considered, that there are no clear alternatives. It simply means that you do not see them. Don’t project your subjective state of uncertainty upon the world at large and claim objective status for it.
What are the practical implications of this? I cannot know directly what a cause is capable of effecting when it is precisely that cause I am looking for, but I can get an indirect knowledge of its causal capability through the effect that is right before me. It is by carefully sizing up the nature of the effect that I can get some understanding of the nature of the cause, and that knowledge will guide me in my search.
Sometimes our failure to find the root causes of things is attributable to simple laziness. We don’t push the investigation far enough. Other times it is impatience which works against us. We are so pressed by the need to do something that we settle for quick fixes, stop-gap measures, while the basic problem remains essentially undisturbed.
Thus far, we have been dealing primarily with what is called the “efficient cause.” The efficient cause, to rephrase what was said earlier, is an agent whose activity brings something into existence or that modifies its existence in one way or another.
Not every type of cause can be applied to everything we are attempting to analyze in terms of causality, but the more types of causes we can identify with something, the more comprehensive is our understanding of it.
Let us analyze a birdhouse in terms of the four causes. Its efficient cause is Fred, who made it. Its material cause is pinewood, the metal of nails, screws, and staples, and paint. Its formal cause is the peculiar configuration of its material, which accounts for its being a birdhouse and not a file box or a window planter. Its final cause is to provide shelter and a nesting site for birds.
As already mentioned, not everything can be analyzed in terms of all four causes.
The most effective way to avoid vagueness or ambiguity in logical discourse is to define one’s terms. We speak of defining terms, but actually what we are defining is the objects to which terms (words) refer.
The logical definition of terms is a two-step process. Step one: Place the term to be defined in its “proximate genus.” Step two: Identify the term’s “specific difference.
The purpose of the reasoning process, logic’s principal concern, is demonstration. I am not reasoning with you if I simply say that such-and-such is true and expect you to accept it as true only on my say-so. I must show you that such-and-such is true, and I do that by making an argument.
The most effective argument is one whose conclusion is a categorical statement.
There are two types of general statements, the universal and the particular.
Always be as precise in your statements about things as your knowledge of them allows you to be.
The concrete expression of logical reasoning is the argument. An argument stands or falls to the extent that the reasoning it incorporates is good or bad.
In this section, we examine all that goes into the making of a healthy and effective argument.
Recall the earlier reference to the elemental move of reasoning, the inferential move, whereby we go from one idea that is known to be true to a second idea that is recognized as true on the force of the first idea. This move constitutes the heart of argumentation.
A “necessary conclusion” is one that it is not possible to doubt—it is certain.
The whole can contain a part, but a part cannot contain the whole.
Is there any legitimate way we can move from particular to universal? Yes, so long as we take care not to claim anything beyond what the evidence allows us to claim.
It is a pretty obvious mistake to claim that something is necessarily true for a whole group because it happens to be true for a part of the group.
It easily qualifies as one of the human family’s favorite fallacies.
“Affirmative statements” connect ideas; “negative statements” disconnect ideas.
All things being equal, if the same idea can be communicated both affirmatively and negatively, it is better to opt for the affirmative construction.
The human mind thrives on comparison. Indeed, thought would be impossible without it. It is through the mental act of comparison that we note the similarities and dissimilarities among things.
A “statement” is the linguistic expression of the most fundamental comparison the mind makes when it relates one idea (the subject) to another (the predicate).
A judgment is sound to the extent that the relationship it forges between two ideas reflects a real relationship in the objective world.
(Note this about the “completely alike” judgment: No two things can be so alike that they cease to be two things. If two things were to be identical in the literal sense, there would be but one thing.
Note this about the “completely unlike” judgment: No two things can be so unlike that they do not share the elemental act of existence. If, in comparing A and B, it is declared that B is “totally unlike” A, then there would be but one thing, A, since B would not exist.)
In comparing any two things, especially large, complex things such as historical events, we must be careful not to rush to the judgment that we have a strong comparison (“the two events are very much alike”) simply because o...
This highlight has been truncated due to consecutive passage length restrictions.
Even a goodly number of similar significant characteristics does not make a strong comparison if a key significant characteristic is omitted.
An argument, as we have seen, has two basic elements: premises and a conclusion.
It is not irresponsible to accept statements as true solely on the authority of those who pronounce them.
It is important to be aware of the difference between truth and validity. Though often confused, they are in fact quite different. First, truth has to do only with statements, whereas validity has to do only with that structural arrangement of statements that we call an argument. Second, a statement is true if what it asserts reflects what is objectively the case. An argument is valid, to echo what was just said, if its structure is such that it will ensure a true conclusion—if its premises are true.
CONJUNCTIVE ARGUMENT
DISJUNCTIVE ARGUMENT
The strength of your conditional argument depends on your knowledge of the two things you are bringing together in the conditional statement that leads off the argument, and of how they are related.
The syllogism is a form of argument that reflects the way the human mind habitually operates: that is, connecting ideas in such a way that conclusions can be drawn from those connections.
The minor premise repeats the operation of the major premise; that is, it incorporates a smaller group into a larger one.
Now, with these two operations completed, the three terms of the argument have been connected and we can literally see how the conclusion indeed follows. There is no avoiding it. If M is a part of P, and if S is a part of M, then S must be a part of P as well.
If we start with a false premise, a valid (i.e., structurally sound) argument will only allow us to proceed consistently to a false conclusion.
“Musicians are people who make music” is a factual statement. Using such a statement as our starting point, we can make an argument that is sound, if not terribly interesting: Musicians are people who make music. Dorothy is a musician. It follows that Dorothy makes music.
Now consider this statement: “Musicians are superior people.” This is a statement not of fact but of value. It expresses the opinion of the one who makes it. There is nothing to prohibit us from making arguments that take off from statements of value. Thus: Musicians are superior people. Cecilia is a musician. Cecilia, therefore, is a superior person.
argument based upon a statement of value can never have the same kind of conclusiveness as an argument based upon a statement of fact, for evaluations can be contested interminably.
For example, the evaluative judgments of someone who has a great deal of knowledge in a given area are to be respected, provided of course that those judgments pertain to the area of expertise in question.
As noted earlier, the “quantity” of a statement refers to its being either universal or particular. The quantity of a statement is established by the quantity of its subject term. “Every pigeon is a bird” is a universal statement. “Some trees are deciduous” is a particular statement.
In a syllogistic argument, if there is a particular statement in the premises, it must be reflected in the conclusion. If one of the premises begins with “some,” the conclusion must begin with “
The quality of a statement, remember, refers to its being either affirmative or negative. If the statement that serves as the conclusion of an argument is negative, at least one of the premises in the argument must be negative. Let us see what happens if both of the premises of an argument are negative. No men are daughters. No waitresses are men. Therefore, no waitresses are daughters. The conclusion is manifestly false. The effect of two negative premises is comparable to that of an undistributed middle term. With an undistributed middle term, no necessary connection is made between
...more
All the arguments discussed thus far have been deductive. The conventional way of distinguishing between deductive argument and inductive argument is to say that the former starts from the general and proceeds to the particular, while the latter starts from the particular and proceeds to the general. This is an adequate account of the difference between the two, but a limited one. A more precise way to distinguish them is to say that deductive argument is productive of necessary conclusions, while inductive argument has the capacity to produce probable conclusions only.
Both deduction and induction, as argumentative forms, possess the two elements basic to all argument: premises and a conclusion.
