The Big Bang Theory, Season 11

Raj:
Are you saying that you don't believe two people fall in love?

Ruchi:
Of course they do. It's just that what people call "love" is actually a series of biochemical reactions in the brain, that fade over time.

Raj:
Yes. Like the old song "When a Man Has a Biochemical Reaction For a Woman".

Ruchi:
Raj, we're scientists. We don't need to feel threatened just because we understand the mechanisms that give rise to romantic feelings. It doesn't take anything away from the experience.

Raj:
Yes, it does. Actually, it takes everything away from it. Love isn't just science, okay? It's spiritual. It's an acknowledgement of a mystery that's greater than ourselves. It's what makes people write songs, and poems, and what has kept The Bachelor on TV for twenty-one magical seasons.

Ruchi:
Don't you think the fact that love is given away as a prize on a game show slightly undermines your argument?

Raj:
Uh, yes. But I've never missed an episode, and I dare science to explain that.