Why do people say "next Tuesday" for the Tuesday falling in the same week? [duplicate]

Possible Duplicate:
Which day does “next Tuesday” refer to?
How did “next day” come to mean “day of next week”?

My employer told me on Monday that something was due "next Tuesday" so I assumed he was talking about the Tuesday next week. However, it turns out he was talking about today.

In American English, does everyone refer to "next (weekday)" as the (weekday) that is closest to the present day? Usually, I am accustomed to calling the closest (weekday) as "this (weekday)" and when someone says "next (weekday)" I presume it falls in the next week or the week after.

This is a tricky area and there is no universal answer, as you can see. Usually, I and the people I know refer to any day in the current week as this weekday. Next weekday refers to days in the week immediately following the current one, and any dates further than that are referred to as weekday the xxth.

As I opened, however, there are inherent ambiguities, and your experience may vary, as may that of others who also answer.

This blog post illustrates some of the ambiguities.