Good grief.

:You are "reasonably sure" that it happened,
: because the observations you make now are interpreted to fit the
: pre-existing supposition that it happened.

No. The Big Bang Theory was developed to explain the observations: chiefly the microwave background radiation and the observation that objects are more red shifted the further they are from the observer.

: Surely you understand the difference - exactly the difference between direct
: observation of something and explanation of something by incorporating
: observations.

All observations are interpreted - your brain forms impressions of the world by interpreting sensory inputs. All observations are indirect.

: I have denied nothing. And you are once again making an effort to label me as
: a fool for explaining logic and observation.

You are avoiding the point.

To get back on track - you have claimed that all life comes from life. I have pointed out that the universe started off sterile. There was no matter in the beginning never mind assemblages of matter big enough to constitutes biological organisms.

Please address that point.