Syllogisms

Correct:

All fishes can breath underwater
A goldfish is a type of fish
A goldfish can breath underwater

All wood is flammable
The fence is made of wood
The fence is flammable

No man is an island
Pedro is a man
Pedro is not an island

All fruit has seeds
A tomato has seeds
A tomato is a fruit

Incorrect:

All monkeys have tails
Pigs have tails
Pigs are monkeys
(Monkeys and pigs are two separate species.)


Every lightbulb is transparent
Lightbulbs use electricity
Every transparent object uses electricy.
(Not every transparent object uses electricity. i.e. windows)

Human beings eat food
Snakes eat food
Snakes are human beings
(Snakes and human beings are not even closely related)

All birds lay eggs
Echidnas lay eggs
Echidnas are birds
(Echidnas are mammals.)