(December 6, 2022 at 12:44 pm)The L Wrote:(December 2, 2022 at 4:35 pm)Thumpalumpacus Wrote: Arguing from conclusion to premise. To wit:
If skyscrapers require concrete, then there is justification for this.
There is not justification for this.
Therefore skyscrapers do not require concrete.
It's Modus Tollens form and a valid argument.
Your problem lies in relying upon "justification".