In my opinion the words " at his option" mean that the worker
must exercise a choice between the two alternatives which the law
allows to him. The mere adoption of one alternative without
knowledge that the law permits another alternative is not an act
of choice between the two alternatives. Therefore, in my opinion,
the worker cannot be held to have exercised an option unless he
knew that there were two alternatives. This does not mean that
he must fully understand the meaning of the provisions of this
section, which have already given rise to so much difference of
judicial opinion. It means simply that he must know that there are
two courses open and that, with such knowledge, he adopts one of
them. The contrary view, namely, that knowledge of his right is
irrelevant, appears to me to ignore the words "at his option."
There is, in my opinion, a very real difference between the following
provisions: (1) The worker may proceed under this Act or
independently of this Act ; and (2) The worker may at his option
proceed under this Act or independently of this Act. Under
a provision such as (1) it is provided that the worker may do one
of two things. Apart from legislation, he would be entitled to
proceed upon either or both of his possible causes of action, which
are separate and distinct. For example, negligence is irrelevant in
proceedings under the Act, and the question whether the injury
arose out of and in the course of the employment does not determine
liability in an action for negligence. The significance of a provision
such as (1) would be that if the worker did one thing he was precluded
from doing the other. On any other construction the provision
would mean nothing. Knowledge of the existence of the alternative
courses would be irrelevant. But, under a provision expressed as
in (2), the position is, I think, quite different. The words "at his
option" add to the meaning of the provision. They introduce an
additional element. This additional element must be that there
should be knowledge that the alternatives exist and a choice between.
them. This view is supported by the consideration of another
provision in the Act. Sec. 39 is, or ought to be, very important in
the administration of the Act. It provides that the commission
shall furnish workers and employers with information as to their
tights and liabilities in respect of all injuries sustained by workers