S
Vega is a M
fixed star,
∴ S
Vega G
twinkles.
“Twinkles” being the predicate of the conclusion is designated as being the major term by putting the letter G above it. Then “G” is placed above the term “twinkle” in the first premise.
“S” is placed above the subject of the conclusion to indicate that it is the minor term. “S” is also placed above “Vega,” the minor term, as found in the second premise.
The remaining term, “fixed stars,” must be the middle term, therefore I place “M” above it. The fact that “fixed star” does not occur in the conclusion verifies this.
Using only the symbols, the syllogism takes this form:
All M is G
S is M
∴ S is G
Using the symbols to represent the other syllogisms, we have