Is the birth of two souls in one an idiom?

"The birth of two souls in one" is not a common idiom in English. It's a figurative expression that suggests a person has a complex and multifaceted inner life, perhaps embodying two distinct personalities or perspectives.

While it's not an established idiom, it can be a powerful and poetic way to describe someone who is deeply introspective or possesses a unique duality.

However, if you're looking for a more familiar idiom to convey a similar meaning, you might consider:

* "Two sides to every coin": This emphasizes the idea of having contrasting aspects or perspectives.

* "Having a split personality": This highlights the presence of two distinct and separate selves within one person.

* "Walking a tightrope": This suggests navigating between two contrasting forces or identities.

Ultimately, the best way to use this expression depends on the specific context and the nuance you're trying to convey.