> That is the lamest excuse for losing an argument I have ever heard.

So, you think that one loses an argument when one expresses a correct idea using the wrong word (assuming there is such a thing)?

> Within a given context words have a precise meaning. If we discuss computer science, we accept that, unless otherwise specified, the textbook meanings of the words "byte", "algorithm" or "concurrency" apply.

Great example!

"It takes 4 bytes to transmit a 32 bit integer."

Agree or don't agree?

> How would you feel discussing computer science with someone, just to discover that he made up his own personal definition of algorithm, that does not match the commonly accepted one? A waste of time, you say?

Why would it matter? As long as what he is explaining is understandable and interesting, why would I terminate an interesting discussion just because someone is using non-standard terminology?

> The same applies here, you cannot discuss philosophy, theology and religions without knowing the precise meanings of "metaphysical entity", "atheism", "agnosticism", etc...

Which is precisely why I tried to make sure we agreed on a definition for the purposes of this discussion.

Also, I really think it would be in your own interest to recognize that my definition of atheism is actually a widely accepted definition, or you'll end up unnecessarily just plain misinterpreting what all those people who use that definition are saying.

> And it's ridiculous to say that you argument it's still valid for some re-definition of the basic concepts.

I'm not sure, but the way you word this suggests to me that you have a fundamental misunderstanding of how definitions work, as "definition of a concept" is not really a meaningful phrase (though you might be using it colloquially, which is why I am not sure).

Concepts are abstract ideas. Definitions are assignments of concepts to labels (words/phrases). For exmaple, "water" is commonly defined to mean "a liquid consisting of molecules of each two hydrogen and one oxygen atoms". Here, "a liquid consisting of molecules of each two hydrogen and one oxygen atoms" is the concept, "water" is the label, and the definition is the convention to use that label to refer to that concept.

As such, it doesn't really make sense to speak of "redefining a concept". You cannot redefine "a liquid consisting of molecules of each two hydrogen and one oxygen atoms", that's a category error. You only can redefine the labels. So, one could, say, redefine "water" to refer to "piece of furniture consisting of one flat surface at the top with four legs". Under that definition, "a water is a piece of furniture" would be a perfectly sensible and true statement. It's questionable whether the definition would be useful, given that the word "table" exists and is commonly accepted to refer to just that concept, but that doesn't make the statement in any way wrong, at best it makes it awkward.

> And I am not going to teach you, exactly as I am not teaching people who don't know what an algorithm is and still want to discuss advanced topics in computer science.

Why do you think that I don't know what a metaphysical entity is? Someone not being sure of which of a variety of possible definitions is implicitly being assumed by some speaker is not the same as them not having any clue of the topic at hand, is it?