It depends on the degree of irrationality.
If some one fears falling off the edge of the earth if they sail too far, that is a bit too irrational. But let's say someone doesn't like to walk outside alone at night due to fear of ghosts or monsters, that is still irrational but might it might have some subconscious rational reasoning like maybe they grew up in a dangerous neighborhood, and can be somewhat useful in keeping that person safe.
The whole point of fear is to act as a protection mechanism against perceived threats, and as long as that purpose is served, fear is more or less rational.
If some one fears falling off the edge of the earth if they sail too far, that is a bit too irrational. But let's say someone doesn't like to walk outside alone at night due to fear of ghosts or monsters, that is still irrational but might it might have some subconscious rational reasoning like maybe they grew up in a dangerous neighborhood, and can be somewhat useful in keeping that person safe.
The whole point of fear is to act as a protection mechanism against perceived threats, and as long as that purpose is served, fear is more or less rational.
Quote:To know yet to think that one does not know is best; Not to know yet to think that one knows will lead to difficulty.
- Lau Tzu
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