Answer: doesn’t matter.
OK, I’m getting a little fed up with still seeing the widely spread analogy of how you see a glass and its content amount reflecting optimism/pessimism over and over.
A glass is half filled with water and it’s half empty. Good. Whether you are an optimist or a pessimist it has NO EFFECT on the state of the glass or its content. So who cares?
What people should care is whether the glass became half full or half empty.
It’s the tangent. The delta.
Be a realist then think about that optimist/pessimist crap.