From the earliest episodes of Star Trek: The Original Series, Dr. Leonard “Bones” McCoy has been the unsung hero of the USS Enterprise, a no-nonsense medical professional whose aversion to technology is counterbalanced by his deep compassion for others, and rare emotional intelligence. Bones is also responsible for some of the show’s most powerful lines of dialogue.

One quote from the season 1 episode “The Enemy Within”, which originally aired in November 1966, gets right to the heart of what it means to be human. This episode is one of Bones McCoy’s best throughout the Star Trek franchise, as it illustrates the lateral thinking and empathy crucial to his diagnostic skills.

Without Bones, the two versions of Captain Kirk would never have been reunited into one single being. It’s emblematic of how important the doctor is to The Original Series. Fans still waiting for McCoy to appear in Star Trek: Strange New Worlds would do well to revisit “The Enemy Within” in particular.

More than anything Bones does in the episode, it’s his best line of dialogue that stands out as a timeless observation that transcends science fiction itself. It epitomizes how Star Trek has stood the test of time as a franchise, by being fundamentally more human than virtually any other screen release set in outer space.

“Bones” McCoy’s Best Star Trek Quote Is Sci-Fi At Its Most Profound

McCoy might be more famous for his Star Trek catchphrases than anything else, but these recurring gags belie the heartfelt wisdom he imparts. Bones is the perfect counterpoint to Spock’s cold rationality, and the passionate argument he makes to Captain James T. Kirk during “The Enemy Within” exemplifies his profound understanding of humankind’s emotional and moral complexity.

As Kirk struggles to come to terms with the fact that he has an “evil” alter ego, Dr. McCoy pleads with the captain to accept that, like all human beings, there’s more to him than just superficial benevolence. “We all have our darker side,” the doctor explains. “We need it! It’s half of what we are. It’s not ugly. It’s human.”

This argument doesn’t just give Kirk himself food for thought, ultimately convincing him to join with the darker side of his personality that’s separated into another body. It also makes viewers at home think long and hard about the nature of good and evil on a personal level.

After all, self-interest, seemingly animalistic desires, aggression, and anger, are all essential parts of our makeup, without which we couldn’t survive, and we certainly couldn’t find our place in society among other human beings. Kirk finds out this lesson all too painfully in “The Enemy Within”, as his “good” and “evil” halves begin to die without each other.

We come away from this episode of Star Trek with a more rounded perspective on different sides of the human psyche. It’s Dr. “Bones” McCoy who deserves all the credit for enlightening us, primarily with his best quote in the franchise.

Star Trek’s Take On Humanity’s Dark Side Still Sets It Apart In The Sci-Fi Genre

Dr. McCoy’s take on the darker side of humanity is a prime example of why so many other sci-fi TV shows are still overshadowed by Star Trek. Especially in the case of its original iteration, the franchise isn’t primarily about good and evil. On the other hand, it embraces the good and bad in all of us, presenting its characters as complex and fallible beings rather than straightforward heroes and villains.

Ironically, one of the first two major TV shows to be set entirely in outer space ultimately appeals to us because of how grounded the figures in its story turn out to be. Star Trek: The Original Series broke new ground for the sci-fi genre in countless ways, yet the show’s true sense of humanity has endured more than any other.

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  Created by

  Gene Roddenberry

  First Film

  Star Trek: The Motion Picture

  First TV Show

  Star Trek: The Original Series

  First Episode Air Date

  
  September 8, 1966
  

  Cast

  William Shatner, Leonard Nimoy, George Takei, Nichelle Nichols, Deforest Kelley, James Doohan, Walter Koenig, Jonathan Frakes, Patrick Stewart, Michael Dorn, Marina Sirtis, Gates McFadden, Brent Spiner, LeVar Burton, Wil Wheaton, Avery Brooks, Nana Visitor, Rene Auberjonois, Alexander Siddig, Cirroc Lofton, Armin Shimerman, Colm Meaney, Terry Farrell, Kate Mulgrew, Robert Beltran, Roxann Dawson, Jeri Ryan, Robert Duncan McNeill, Robert Picardo, Ethan Phillips, Garrett Wang, Jolene Blalock, Connor Trinneer, Dominic Keating, Scott Bakula, Linda Park, John Billingsley, Anthony Montgomery, Chris Pine, Zachary Quinto, Simon Pegg, Zoe Saldana, Karl Urban, John Cho, Chris Hemsworth, Benedict Cumberbatch, Anton Yelchin, Idris Elba, Sonequa Martin-Green, Mary Wiseman, Doug Jones, Anthony Rapp, Wilson Cruz, Oyin Oladejo, Emily Coutts, Jess Bush, Christina Chong, Anson Mount, Ethan Peck, Rebecca Romijn, Michelle Yeoh

  TV Show(s)

  Star Trek: The Original Series, Star Trek: The Animated Series, Star Trek: The Next Generation, Star Trek: Deep Space Nine, Star Trek: Voyager, Star Trek: Enterprise, Star Trek: Discovery, Star Trek: Short Treks, Star Trek: Picard, Star Trek Lower Decks, Star Trek: Prodigy, Star Trek: Strange New Worlds, Star Trek: Starfleet Academy

  Star Trek is one of pop culture’s biggest multimedia franchises, spanning multiple movies, TV shows, books, comics, video games, and various other media. The franchise was created by Gene Roddenberry and started with the 1960s TV series starring William Shatner and Leonard Nimoy. Over the decades, several equally popular series have come out since as Star Trek: The Next Generation and Star Trek: Discovery.