Syllogism
In his book Prior Analytics, Aristotle introduced the concept of syllogism. Syllogism is a form of reasoning through which conclusions can be drawn based on specific assumptions or premises. A common example that is often used:
1. All Greeks are human.
2. All humans are mortal.
3. Therefore, all Greeks are mortal.
A syllogism consists of three statements: the first two statements are premises, while the last statement is the conclusion. Premises can be either universal (using words like every, all, or none) or particular (using words like some), and they can also be affirmative or negative.
Three Fundamental Principles
According to Aristotle, 3 fundamental principles apply to all correct thoughts:
Law of Identity:
This principle states that “X is what X is,” and this is correct because X has certain specific characteristics. A tree is a tree because we can see its leaves, trunk, branches, etc. A tree has no other existence except as a tree. Therefore, whatever exists is true for itself; it cannot be something else at the same time.
Law of Non-Contradiction:
This principle states that X cannot be both X and non-X at the same time. No statement can be both true and false at the same time. If this happens, a contradiction will arise. For example, if you say that you fed the cat yesterday and then say that you did not feed the cat yesterday, this would be a contradiction.
Law of Excluded Middle:
This principle states that a statement must be either true or false. There can be no middle ground. According to this law, anything must be either true or false. If you say that your hair is golden, then this statement will be either true or false. However, later philosophers and mathematicians have objected to this law.
