The problem with "NEXT"

Not so long ago while arranging a series of classes with a very important executive we agreed on Thursday mornings as being best for both of us. The only thing that needed to be done was to establish when we would start.
Tuesday morning I received an Email from my client stating that he would like to begin "NEXT Thursday". So I registered this time in my agenda and forwarded the email to the school where they duly registered the same details.
Two days later I was in the middle of another class when I received a message from the Executive asking me if I had forgotten my appointment with him. I quickly contacted the school to see if they had received any kind of message changing the day and was informed that the day booked was indeed next week. It took a few moments for me to understand what might have happened until I realized the curse of the "NEXT" in the executive's Email.
English is very clear about its use of "NEXT" especially when dealing with time.
THIS week, THIS month, THIS year and THIS century are as explicit as NEXT week, NEXT month, NEXT year and NEXT century are.
Thursday is understood to be THIS Thursday while NEXT Thursday will always refer to the Thursday of next week. When we use ON Thursday by itself, then the tense that follows indicates whether it is a Thursday of the past or a Thursday of the future. In the Executive's message received on Tuesday,  NEXT Thursday could only refer to the following Thursday,  not this Thursday in two days time.
In much the same way we often ask what HAPPENED last Thursday to refer to the week before and what WILL happen on Thursday, referring to the Thursday still to come this week. 

Brazilians have a big problem with NEXT (proximo) in their own language. Not everybody is sure whether PROXIMO is being used to mean THE NEXT event or the FOLLOWING event, which leads to many double questions and sometimes explanations of what is really meant. It would seem that this confusion is carried through to English where NEXT is used in place of THE NEXT, a legitimate structure but inconsistent with this concept of time.
After I understood what had happened to my Executive, I quickly replied to him with a brief explanation of what the problem was. This may not have been much of a problem with regards to classes, but I couldn’t help imagining the serious consequences of something similar happening to an international visitor.
It is, therefore very important to not only understand the correct way of referring to a future appointment,  but also understand that the simplest concepts in English may not be so simple in other cultures. ALWAYS include a DATE as well as the day,  the one or more TIME references, usually in 24-hour notation, as well as the time zones when necessary.