By definition.......

Definitions of positivism:

• noun: a quality or state characterized by certainty or acceptance or affirmation
• noun: the form of empiricism that bases all knowledge on perceptual experience (not on intuition or revelation)

Definitions of optimism:

• noun: a general disposition to expect the best in all things
• noun: the optimistic feeling that all is going to turn out well
  
  Definitions of negativism:
  
  
• noun: characterized by habitual skepticism and a tendency to deny or oppose or resist suggestions or commands
  
  Definitions of pessimism:
  
  
• noun: a general disposition to look on the dark side and to expect the worst in all things
• noun: the feeling that things will turn out badly

I AM BY DEFINITION AN OPTIMIST WITH NEGATIVISM NUANCES