how to follow the prime directive, by leonard h. mccoy, md
But he is following the prime directive. The core of the prime directive is non-interference. Are your actions going to impact the development of an alien culture? More importantly, will they impact that culture in such a way as to destabilize that culture or create a permanent power disparity? The way the prime directive is interpreted varies a lot, within and especially between series, but in every case it’s clear that the violation in question would have some far-reaching affect on the society.
And that’s not the case here. What’s more likely - the doctors are going to theorize that a man from the future gave that lady a magic kidney regenerating pill, or they just chalk it up to a misdiagnosis? The development of the society is not going to be affected at all, just one person’s life. And even if it were, the prime directive applies specifically to alien societies and doesn’t address time travel.
I’m a huge fan of the prime directive. Non-interference is a good - actually necessary - principle for an organization like starfleet. They are going to come across species with much less advanced weapons, transportation, and communication technology, and historically that’s a situation that leads to massive and long-lasting institutional power imbalances at best. The prime directive is there to keep people safe, and even the episodes where it’s used as a justification for refusing to save people or whole civilizations don’t present that as a universally accurate interpretation.
Bones gets that.