The English works of Thomas Hobbes of Malmesbury, Volume 05 (of 11)
Thomas Hobbes · en
“But though his instance of raining to-morrow be impertinent, as being
no free action, yet because he triumphs so much in his argument, I will
not stick to go a little out of my way to meet a friend. For I confess
the validity of the reason had been the same, if he had made it of a
free action, as thus: _either I shall finish this reply to-morrow, or I
shall not finish this reply to-morrow_, is a necessary proposition. But
because he shall not complain of any disadvantage in the alteration of
his terms, I will for once adventure upon his shower of rain. And first,
I readily admit his major, that this proposition, _either it will rain
to-morrow or it will not rain to-morrow_, is necessarily true: for of
two contradictory propositions, the one must of necessity be true,
because no third can be given. But his minor, that ‘it could not be
necessarily true, except one of the members were necessarily true’, is
most false. And so is his proof likewise, that ‘if neither the one nor
the other of the members be necessarily true, it cannot be affirmed that
either the one or the other is true’. A conjunct proposition may have
both parts false, and yet the proposition be true; as, _if the sun shine
it is day_, is a true proposition at midnight. And T. H. confesseth as
much, No. XIX. ‘_If I shall live I shall eat_, is a necessary
proposition, that is to say, it is necessary that that proposition
should be true whensoever uttered. But it is not the necessity of the
thing, nor is it therefore necessary that the man shall live or that the
man shall eat’. And so T. H. proceeds: ‘I do not use to fortify my
distinctions with such reasons’. But it seemeth he hath forgotten
himself, and is contented with such poor fortifications. And though both
parts of a disjunctive proposition cannot be false; because if it be a
right disjunction, the members are repugnant, whereof one part is
infallibly true; yet vary but the proposition a little to abate the edge
of the disjunctions, and you shall find in that which T. H. saith to be
true, that it is not the necessity of the thing which makes the
proposition to be true. As for example, vary it thus: _I know that
either it will rain to-morrow or that it will not rain to-morrow_, is a
true proposition: but it is not true that I know it will rain to-morrow,
neither is it true that I know it will not rain to-morrow; wherefore the
certain truth of the proposition doth not prove that either of the
members is determinately true in present. Truth is a conformity of the
understanding to the thing known, whereof speech is an interpreter. If
the understanding agree not with the thing, it is an error; if the words
agree not with the understanding, it is a lie. Now the thing known, is
known either in itself or in its causes. If it be known in itself as it
is, then we express our apprehension of it in words of the present
tense; as _the sun is risen_. If it be known in its cause, we express