Star Trek: 10 Greatest Captain Kirk Speeches

Leave any bigotry in your quarters. There's no room for it on the bridge.

This is, perhaps, the very essence of Star Trek in a nutshell. Kirk, in his capacity as captain, reminded Lieutenant Styles that whatever he carried in his heart, he could not express that as part of his duties. 

In a way, that may seem almost totalitarianism. Surely in the future, we should be free to express how we feel about a certain situation? However, therein lies the point that the episode was making. In the future, we will be free to do so - as we will have evolved, and we will have developed our understanding of the universe.

Styles becomes the archetypal character of an older, less educated way of thinking here. The Romulans may look like Vulcans, yet that does not mean that both species are the same. Therefore his immediate assumptions as to the nature of Vulcans display his prejudice. That is entirely anathema to Starfleet, to the Federation, and to the very notion of exploration. 

There truly is no room for bigotry when there is the wide unknown to understand.