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Problem description 1: Reasoning in the past tense

The reasoning example mentioned above was true during the life of Socrates. But now, after the ultimate proof of his morality – his death in the year 399 BC – we should use the past tense form:

> Given: “All men are mortal.
> Given: “Socrates was a man.

• Logical conclusion:
< “Socrates was mortal.

The tense of a verb tells us about the state of the involved statement:
• “Socrates is a man” tells us that Socrates is still alive;
• “Socrates was a man” tells us that Socrates isn't amongst the living anymore.

In regard to the conclusion:
• “Socrates is mortal” tells us that the death of Socrates is inevitable, but that his mortality isn't proven yet by hard evidence;
• “Socrates was mortal” tells us that his mortality is proven by hard evidence.

In the past 2,400 years, scientists have "forgotten" to define algebra for the past tense. So, reasoning in the past tense form is not described in any scientific paper, while it is implemented in my CNL reasoner.