antigone discussion

The quote that I think that we should discuss is when Antigone says "When I have tried and failed, I shall have failed," to which Ismene replied, "No sense in starting on a hopeless task" (129) This brings up an important struggle not just in Antigone, but in life. Is it worth it to attempt a task that you know you will fail? The two sisters plant themselves squarely on opposing sides of the issue, as Ismene claims that trying something with no hope of success is pointless, while Antigone asserts that it is better to try on the basis of principle than to give up without trying at all. Which side is more correct? Is it better to live by principles or to be a realist?