When I left my office a few minutes ago there was no coffee on my table; now when I return there is a cup of coffee lying on my table; therefore I conclude that somebody must have brought a cup of coffee for me during my absence. Which of the following instruments of knowledge is used in the above example?

The reasoning is postulation, arthapatti, assuming an unseen fact to explain what is otherwise unaccountable.

Earlier there was no coffee on the table; now a cup of coffee is present.

This changed situation cannot be explained on its own.

It compels the presumption that someone brought the coffee during the absence.

Postulating an unperceived fact to make a known fact intelligible is arthapatti.