20150909 THEIRS NOT TO REASON WHY,

Theirs but to do and die.

First thing first: the line came from this poem. At the Battle of Balaclava (no, not that balaclava, Balaclava is a town near Sevastopol in Crimea (yes, this Crimea)), which happened during Crimean War, a 600-strong British light cavalry detachment was sent to attack a powerful and well guarded Russian battery through so-called valley of Death. Apparently, due to their commander's mistake.

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Theirs not to make reply,
Theirs not to reason why,
Theirs but to do and die:

Not all of them died, and those who did not, inspired another famous poem, but you better read the article.

What British cavalry was doing in Crimea is another story, and a very interesting one. Wikipedia has it too.

It took me years to realize that the "do and die" attitude was one of the biggest difficulties my wimpy kids were facing at schools. They were raised to understand. American school demanded blind obedience. I failed to prepare them for this.

Before answering why (invert and multiply), let me tell you that this must be the second inversion to learn. The first one is invert and add.