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An introductory text-book of logic - Mellone, Sydney - Rare Books at ...

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THE LOGICAL PROPOSITION. 63<br />

&quot;some <strong>at</strong> least.&quot; In either <strong>of</strong> these last cases, the pro<br />

position is particular; otherwise it is universal.<br />

Some verbal expressions indic<strong>at</strong>ing universality may be<br />

mentioned. Words such as All, Every (Each\ <strong>An</strong>y, He<br />

who ( Whoever), The, and (sometimes) A, when joined to the<br />

Subject, signify an A proposition, just as No, None, signify<br />

an E. Similarly Always, Never, in the predic<strong>at</strong>e, signify A<br />

and E respectively. I is indic<strong>at</strong>ed by Some, Certain, A few,<br />

Many, Most, c., or by Generally, Often, standing in the<br />

predic<strong>at</strong>e ; O<br />

by any <strong>of</strong> these words with a neg<strong>at</strong>ive. Some<br />

signs <strong>of</strong> quantity are not free from ambiguity ; and this is<br />

a point requiring special <strong>at</strong>tention, (i) All in a neg<strong>at</strong>ive<br />

proposition means some, in common language, th<strong>at</strong> is,<br />

&quot;some only&quot; ; and propositions <strong>of</strong> this form must usually be<br />

tre<strong>at</strong>ed as exclusives, and be analysed into two propositions.<br />

One <strong>of</strong> these will be more immedi<strong>at</strong>ely implied, by the<br />

original proposition, than the other.<br />

&quot; Thus All the metals<br />

are not denser than w<strong>at</strong>er,&quot; or &quot;Not all the metals are<br />

denser than w<strong>at</strong>er,&quot; is equivalent to<br />

( (a) Some metals are not denser than w<strong>at</strong>er,<br />

( (b) Some metals are denser,<br />

where () may be called the primary, (b) the secondary im<br />

plic<strong>at</strong>ion. Similarly, &quot;All cannot receive this saying,&quot; is<br />

equivalent to<br />

( (a) Some are not able to receive this saying.<br />

} (b) Some are able to receive it.<br />

A proposition <strong>of</strong> the form<br />

possibly mean &quot;<br />

No<br />

&quot;<br />

&quot;<br />

All S are not P <strong>of</strong> course might<br />

S are but if P,&quot; so it should have st<strong>at</strong>ed<br />

its meaning without ambiguity (see ex. 8, below). (2) The<br />

words Few, Hardly any, Scarcely any, before the subject, or<br />

Seldom in the predic<strong>at</strong>e, require the proposition to be<br />

&quot;<br />

&quot;<br />

analysed into two. Few men know how to think asserts<br />

th<strong>at</strong> some do and others do not know how to think. It must<br />

be analysed into an O and an I<br />

proposition, the former being<br />

the primary implic<strong>at</strong>ion. (3) When Certain means a definite<br />

individual or group which I have in view, it makes the<br />

Subject a singular term (sometimes a singular collective) :<br />

&quot;A certain man encountered him&quot; ; &quot;Certain Greek philo<br />

sophers were the founders <strong>of</strong> Logic.&quot;<br />

In the l<strong>at</strong>ter st<strong>at</strong>ement

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