Being unconcerned does not necessarily mean to be iron-hearted, but a disguise to avoid getting hurt.
2009-02-24 23:04:34 補充：
Apathy stands sometimes for, rather than ruthlessness, but....
2009-03-02 12:26:04 補充：
Thanks, Kevin. It's clear now.
However, I would prefer "just; only; merely" to "but" in this sentence when it follows a "tather than" phrase.