  In this work an intrinsic projectively invariant distance is used to
establish a new approach to the study of projective geometry in Finsler space.
It is shown that the projectively invariant distance previously defined is a
constant multiple of the Finsler distance in certain case. As a consequence,
two projectively related complete Einstein Finsler spaces with constant
negative scalar curvature are homothetic. Evidently, this will be true for
Finsler spaces of constant flag curvature as well.
