The equal protection standard ...

The equal protection standard of the constitution has one clear and central meaning - it absolutely prohibits invidious [repugnant] discrimination by government...Under our Constitution, any official action that treats a person differently on account of his race or ethnic origin is inherently [by nature] suspect and presumptively [probably] invalid...Under the Constitution we have, one practice in which government may never engage in the practice of racism - not even "temporarily" and not even as an "experiment.
 Potter Stewart

Quotes from the same author

I shall not attempt further to define the kinds of material I understand to be embraced within that shorthand description (of pornography), 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.
 Potter Stewart
Abortion is inherently different from other medical procedures, because no other procedure involves the purposeful termination of a potential life.
 Potter Stewart
Newspapers, television networks, and magazines have sometimes been outrageously abusive, untruthful, arrogant, and hypocritical. But it hardly follows that elimination of a strong and independent press is the way to eliminate abusiveness . . .
 Potter Stewart
We dedicated ourselves to a powerful idea - organic law rather than naked power. There seems to be universal acceptance of that idea in the nation.
 Potter Stewart
We are concerned here only with the imposition of capital punishment for the crime of murder, and when a life has been taken deliberately by the offender, we cannot say that the punishment is invariably disproportionate to the crime. It is an extreme sanction suitable to the most extreme of crimes.
 Potter Stewart