Epictetus, a Greek sage and Stoic philosopher used to say (and it's quoted by his most famous pupil, Arrian, in his book "Enchiridion") that:

What upsets people is not things themselves but their judgements about the things. For
example, death is nothing dreadful or else it would have appeared dreadful to Socrates. No, the only dreadful thing about it is men's judgement that it is dreadful.

This very phrase, said Albert Ellis, had an impact on his forming Rational Emotive Behavior Therapy. Ellis thought that a person is more affected by his perceptions of a situation, a lot more than the situation per se.

What's your take on this? Do you believe that how we judge things and the situations we live in affects our reality and opinions, or that our opinions and judgements are formed accordingly to the situations we live in?

I'd say it's a little vice versa and there's not a solid external reality, but then again there's some form of objectivity, or else how come we all agree to what a person with a problem (ie drug abuse, depression, schizophrenia etc) is?

You can find a translated version of Epictetus Enchiridion here.