Opposite of phobia

In Ireland it's called a HUSBAND

On a more serious note: FEARLESS

on a less serious note [love]

Lack of fear? Well, I am not afraid to die: I know that this is inevitable, and I am not so much concerned of when this will happen (by all means, I would prefer to die before having developed Alzheimer's disease or senile dementia). I would not mind even if it happens this night when I am asleep. I may be scared of the very process of dying [/i](for example, of chronic disabling disease (cancer, AIDS, myasthenia gravis, tetanus, rabies, hepatic cirrhosis, etc. -- these diseases cause enormous sufferings), or of being lynched, or of burning alive being trapped in the burning building), but not of the result.

I'd guess something like "penchant" or "compulsion". Where is Aa with her OED when ya need her?

philia

I suppose we call it 'fool hardiness', but it can be a genuine problem! I believe it is an inability to reason possible consequences properly.

I would put fetish as the opposite of phobia.

A person who isn't afraid of putting his hand in a flame would be called
"foolish" or "uninformed".

A phobia is a strong and unreasonable fear. The fear of being burned when you stick your hand in a flame is quite reasonable!

I've seen both philia and mania used, though I doubt either is the accepted clinical term today.