Ah, such a wealth of targets!

For starters, try again on your mis-reading of the "reality" sentence in the post to which you replied.

Careful parsing will tell you "the eye of the beholder" applies to "perversity," not to "reality."

Then -- with respect to your last three paragraphs -- I offer the generic suggestion that you should get your facts right (or, at least, stick to relevant ones)!

I shall offer several respected professional interpretations. First, however, lets establish the factual groundwork: The University of of Missouri - Kansas City offers the relevant section of Mr. Justice Stewart's concurrance at http://law2.umkc.edu/faculty/projects/ftrials/conlaw/obscenity.htm:

"MR. JUSTICE STEWART, concurring in Jacobellis v. Ohio, 378 US 184 (1964).

"It is possible to read the Court's opinion in Roth v. United States and Alberts v. California, 354 U.S. 476, in a variety of ways. In saying this, I imply no criticism of the Court, which in those cases was faced with the task of trying to define what may be indefinable. I have reached the conclusion, which I think is confirmed at least by negative implication in the Court's decisions since Roth and Alberts, that under the First and Fourteenth Amendments criminal laws in this area are constitutionally limited to hard-core pornography. I shall not today attempt further to define the kinds of material I understand to be embraced within that shorthand description; and perhaps I could never succeed in intelligibly doing so. But I know it when I see it, and the motion picture involved in this case is not that."

Before you quibble further, you may also want to read Mr. Justice Brennan's opinion, and specifically,

MR. JUSTICE BRENNAN, joined by MR. JUSTICE GOLDBERG, concluded that:

• Though motion pictures are within the constitutional guarantees of freedom of expression, obscenity is not within those guarantees. P. 187.
• This Court cannot avoid making an independent judgment as to whether material condemned as obscene is constitutionally protected. Pp. 187-190. (emphasis supplied)

See also Cornell Law School and FindLaw for further information, including the quotation immediately above.

The usage underlying my prior post is not constrained to consideration of pornography; it has obtained currency in the general population and in the legal community, as illustrated by this section from a 2005 Florida Bar Association Journal article on "professionalism" (numeric pointers to endnotes removed):

"Lon Fuller wrote that to be moral, law must be promulgated. Similarly, Sir Thomas Aquinas wrote that even though generally understood notions of morality may dictate appropriate conduct, promulgation is necessary for law to obtain its force. But ask the average Florida Bar member to apply these concepts to the professionalism movement, and you are likely to be answered with a moment of thoughtful silence. Their silence is understandable, because in its present form, the concept of professionalism follows the thinking of neither Fuller nor Aquinas. Instead, professionalism is defined by the lack of a definition, following Justice Potter Stewart’s “I know it when I see it” approach to defining pornography."

There's much more -- for example, this, from Yale Law School by Paul Gewirtz, the first Potter Stewart Professor of Constitutional Law. But a search conducted with some considerable diligence fails to find a credible source supporting your interpretation.