That which I know (what I believe to be true) is concluded through [logical reasoning]
Logical Reasoning is comprised of BOTH deductive reasoning and inductive reasoning.
If: the premises are true
Then: an absolute certain conclusion.
IF: [A] = [B]
AND: [B] =[C]
THEN: [A] = [C]
IF: my premises are true
Then: I will reach a probable conclusion but it will not be a certainty
Your "probable conclusion" by definition introduces more uncertainty.
Your premise itself depends on uncertainties that is out of scope of the exercise.
If you drop an apple.
Then it will "probably" hit the floor directly below from where you dropped it.
You are depending on gravity to be consistent through time and space, and other external forces to be non-factors.