What does it mean to say you have formal reasoning?

Question

if this help im doing a powerpint on developmental psychology. it states that only 35% develop the capacity to formally reason during adolescence or adulthood.

Answer 1

Formal reasoning is the process by which one can develop an hypothesis and discern the validity of that premise by formally analyzing the cogent variables in a formal, mathematical logic based sense.

An example is the If, Then, Else type of reason flow.