C 3^1 ] 
Intcreft flhe' prefent ¥a!ue of any Somm payable 
after Twelve Years^, is but half the Summ ; So if the 
Probability or Proportion of Ceriitude tranfmitted by 
each Reporter, be ;g 5 the Proportion of Certainty after 
'Twelve fuch Tranlmiffions/ will be bat as a hair 5 and 
it willgrohw by tat Time an equal Lay, whether the 
Report be true or no. Ir the fame Manner^ if the Pro- 
portion of Certainty b.. ii. dt]^, it will cumetoahalf 
from the jot h Hand; Aod ifaijg^^ from 1 he 69^ th. 
PROP OS. 11. 
Concerning Concurrent Tefiifcatms. 
IF Two Concurrent Repcnters have,each of them^as '^hs 
of Certainty ; they will both give me an Affurance 
of Whs^ or of 35 to one : If Three ; an Aflbrance 
of \% or of 2 1 5 to one, ^ 
For if one of them gives a Certainty for 1200/5 as 
of 5 there remains but an Affurance of ith^ or of 
aoo / wanting to me, for the whole. And towards 
that the Second Attefler contributes, according to his 
Proportion of CredibiUty : That is to 'ths of Certainty 
before had, h€ adds l^^i of the \th which was wanting: 
So that there is now wanting but of 2.1th. rh dt is 
and confequently I have, from them boih, llths 
of Certainty* So from Three, -I, &c. 
That is, if the Firft Witne(s gives me ^ of Cenain* 
ty, and there is wanting of it ^^7^ the Second Atteftcr 
will add —-^ of that ^ ; and confequently leave m- 
thi^ wanting but j:;:7of that — - 1*=-^. And 
in like manner the third Attefter adds his ~ of tbat 
-i-p^ , and leaves wanting only Sec. . 
^3 HhhT' Co- 
