How many years apart are 1992 and 1996?

Answer 1

This question hits upon the important distinction between continuous and discrete quantities. If I want to know the difference between 2 apples and 6 apples, the answer is not difficult to determine, and few would argue that 4 apples is at least a strong and defensible answer. Number of apples is 'discrete'. For ordinary discussions, you either have one whole apple, or you have none. (Put cutting them up aside for another discussion). Years are not discrete, but continuous; they flow over time and you can have any number of fractions of a year, depending on how fine you want your units of time to be.

From the beginning of January 1 1992 until the end of December 31 1996, you have the passage of 5 full years.

From June 1 1992 until June 1 1996, you have the passage of 4 full years; This would be true for any start and end dates that are the same month and day. Four is also the difference you would get if you are looking at the integers 1992 and 1996 on the number line. Interesting to note that the number line answer incorporates the full range of only one of the numbers.

From the last moments of 1992 until the first moments of 1996, there is the passage of 3 full years, plus a few moments. Or, there are 3 full years between the two, excluding any moments of either.

So you have to do some thinking, and decide how you are defining your terms before you derive the answer.