no evidence of a different injury or blindness subsequent to February
15th 1935, The argument involves and is based upon the fallacy
that, where an issue between A and B relates to a state of things
which is capable of subsequent alteration, the conclusive determina-
tion in A's favour of that state of things as at one day plus conclusive
proof that up to a later day there has been no alteration of such
state of things establishes in A's favour as against B an estoppel as
to the state of things existing at the later day. If, for instance.
a court held that, on June 30th, 1935, the value of Blackacre was
£50,000, and if, in subsequent proceedings between the same parties
to determine the value of Blackacre as at June 30th, 1936, it was
also proved that there had been no increase or decrease in the value
of Blackacre between June 30th, 1935 and 1936, a court which has
jurisdiction to determine the value as at the second date is not
bound to find that there is an estoppel as to the value of Blackacre
as at the second date. Similarly here. What the appellant is
trying to do is to eke out a conclusive determination that incapacity
through blindness as at an anterior point of time can, by additional
proof of absence of any change in the meantime, be converted into a
conclusive determination of incapacity through blindness at a later
point of time. But this method, though logically sound, is not
permitted by law. Estoppel by judgment estops not only as to the res
determined but also as to the fundamental issues necessarily involved
in the determination, but it does not authorize the use of each issue
originally determined merely as the first but unbreakable link in
establishing a separate and independent issue. In other words,
as against a successful party the unsuccessful party is-bound by the
authoritative determination of every fundamental issue but when a
distinct and separate issue arises subsequently, he is not bound to
submit to the second issue being established by the combination of
a former issue with additional evidence, no matter how strong such
evidence may be.
The result is that the appeal should be dismissed.