3. Statements of opinion:
It seems to me.
In my opinion.
4. Statements using the emphatic "to be" words. Is, are, was, were, etc. are often facts that can be proven either true or false, but are not necessarily as true as the "is" implies.
He is a genius.
For the purpose of gathering information in problem solving, facts are statements that can be readily verified as true or false; opinions cannot be quickly verified. In problem solving, the practical ability to prove something true without a great deal of effort is the key to practical truth. A statement that might merely hold the possibility of being proven true is, for all practical purposes, an opinion until it is proven true.
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DEDUCTIVE REASONING ERRORS
Deductive reasoning [9] is stating a series of valid relationships with a conclusion about them: