Are these all OK and natural?

A feeling, emotion etc.

Only those who have experienced it know.
Those who haven’t experienced it don't know.
Those who haven’t experienced it can't understand.
You don't know how it feels if you haven't experienced it.

Question

Are these all OK and natural?

A feeling, emotion etc.

Only those who have experienced it know.
Those who haven’t experienced it don't know.
Those who haven’t experienced it can't understand.
You don't know how it feels if you haven't experienced it.

Answer

Yes, these are all very natural and are commonly used.

Answer

These are great.  "you don't know until you try" is quite common..  and similar variations of that 👍🏼

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