亚里士多德解释编—-关于时间的命题

In the case of that which is or which has taken place, propositions, whether

positive  or  negative,  must  be  true  or  false.  Again,  in  the  case  of  a  pair  of

contradictories, either when the subject is universal  and the  propositions  are

of a universal character, or when it is individual, as has been said,’ one of the

two  must be true and the  other  false;  whereas when the subject is  universal,

but  the  propositions  are  not  of  a  universal  character,  there  is  no  such

necessity. We have discussed this type also in a previous chapter.

When the subject, however, is individual, and that which is predicated of it

relates  to  the  future,  the  case  is  altered.  For  if  all  propositions  whether

positive  or  negative  are  either  true  or  false,  then  any given  predicate must

either belong to the subject or not, so that if one man affirms that an event of

a  given  character  will  tak e  place  and  another  denies   it,  it  is  plain  that  the

statement of the one will correspond with reality and that of the other will not.

For  the  predicate  cannot  both  belong  and  not belong  to  the  subjec t  at one

and the same time with regard to the future.

Thus, if it is true to say that a thing is white, it must necessarily be white; if

the reverse propos ition is  true, it  will of necessity not be  white. Again, if  it is

white,  the  proposition  stating  that  it  is  white  was  true;  if  it  is  not  white,  the

proposition to the opposite effect was true. And if it is not white, the man who

states that  it  is making a false statement; and if the man who states that it is

white  is  making  a  false  statement,  it  follows  that  it  is  not  white.  It  may

therefore be  argued  that  it is  necessary  that affirmations  or  denials  must be

either true or false.

Now if this be so, nothing is or takes place fortuitously, either in the present

or in the future, and there are no  real  alternatives; everything takes  place of

necessity  and  is fixed.  For  either he  that affirms  that it  will take  place or  he

that  denies this is in correspondence  with fact, whereas if things did not take

place of necessity, an  event  might  just as easily not  happen  as  happen; for

the meaning of the  word ’fortuitous’ with regard to present  or future events is

that  reality  is  so  constituted  that  it  may  issue  in  either  of  two  opposite

direc tions. Again, if a thing is white now, it was true before to say that it would

be white, so that of anything that has taken place it was always true to say ’it

is’ or ’it will be’. But if it was always true to say that a thing is or will be, it is not

possible that it should not be or not be about to be, and when a  thing cannot

not come to be,  it is impossible that it should not come to be,  and  when  it is

impossible that it should not come to be, it must come to be. All, then, that is

about to be must  of  necessity  take  place.  It  results from  this  that nothing  is

uncertain or fortuitous, for if it were fortuitous it would not be necessary.

Again, to say that neither the affirmation nor the denial is true, maintaining,

let  us  say,  that an event neither  will  take  place  nor  will  not  tak e  place,  is  to

take up a position impos sible to defend. In the first place, though facts should

prove the one proposition false, the opposite would still be untrue. Sec ondly,

if it was true to say that a thing was both white and large, both these qualities

must necessarily  belong to it;  and  if  they  will  belong to it  the next  day, they

must necessarily  belong to it the  next day.  But if  an event is neither to take

place  nor  not  to  take  place  the  next  day,  the  element  of  chance  will  be

eliminated. For example, it would be necessary that a sea-fight should neither

take place nor fail to take place on the next day.