Simon Blackburn quoting Parfit

Putting all these together we get that “an act is wrong just when such acts are disallowed by some principle that is optimific, uniquely universally willable, and not reasonably rejectable”.

Obviously something is wrong when disallowed by a principle not rejectable, this goes without saying. Truisms are usually formulated when no theory is available. Both truisms and tautologies are logical fallacies. The quote from Parfit was a truism and not a tautology.

(not sure about my argument here, will get back to it)


Lies are the semantic opposite of truth. To lie is wrong, but the question as to why something like lies or stealing is ultimately wrong we need to contrast it with its semantic opposite: Truth itself.

Tarkski's semantic theorem of truth showed that any attempt at defining truth leads to a contradiction, Truth itself can't therefore be defined in terms very same axioms we have to assume as true such A or non-A.

Something can only ultimately be wrong if it violates Truth itself. But what is Truth? Unless you can define Truth itself, you have no semantic opposite on which to judge something as wrong, erroneous, disallowed or destructive.

We can only comprehend ideas in terms of primary Platonic binary opposites as I explained at Pattern or design

The Lord Jesus said ... I am truth ..... Since God can't be reduced to a falsifiable construct, Tarski came to the correct conclusion. An absolute ultimate reason as why something is correct is because Truth himself became flesh and said: Do unto others as you would have them do unto you.

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