The suggestion would appear to be that we may know exactly how to carry out a process but we're not too sure precisely what to apply this process to or - alternatively - howbest to apply it if we do know.
Q is quite right, since here, in context, is Einstein's entire quote:
"Perfection of means and confusion of goals seem to characterize our age. If we desire sincerely and passionately the safety, the welfare and the free development of the talents of all men, we shall not be in want of the means to approach such a state."