Why Would Time Travellers Try to Kill their Younger Selves?
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I raise a new problem for backwards time travel, and make some first
suggestions as to how it might be solved.  I call it the *motivation problem*.
It arises when time travellers interact with their younger selves.  In many
such situations, the older time traveller knows what she will do next, before
she does it---for she remembers seeing it happen (from the perspective of the
younger self) when she was young.  However it would seem that it is
psychologically impossible for someone to both know exactly what she is going
to do next, and also deliberate in the normal way about what to do next.  So
what could be going through the head of a time traveller as she attempts (say)
to kill her younger self?  I suggest several ways in which time travellers
could interact with their younger selves which, although strange in various
ways, do not involve a complete breakdown of all known psychological
mechanisms.