RE: [PHP] Discussion: do you consider null a value or strictly a type?

[snip] I also think, in discussing NULLs, that we hit a limit of language - we have to refer to this "not knowness" as something. Thus a variable set to NULL is not like an empty bucket, more like a bucket with potential, but if you examine it reveals not " " 's, or 0's, but a benign vacuum. [/schnip] NULL indicates a state of nothingness no matter how you slice it. However it does appear as if PHP assigns a value to it, such as it is. '' is a string value for nothingness, 0 is a number value for nothingness (which brings up the question...do negative numbers indicate something is less than nothing?).