The following diagram shows that 52 \(\not \Rightarrow\) 215 is a code 6 non-implication, and the theory of transferability then shows that it is actually a code 4. It follows that the non-implication 280 \( \not \Rightarrow \) 215 is not just a code 6 non-implication, but is also a code 4 non-implication.
215 | This form is negation transferable | |||
\(\Downarrow\) | ||||
67 | \( \not \Rightarrow \) | 198 | ||
\( \Downarrow \) | ||||
This form is transferable | 52 | |||
\( \Downarrow \) | ||||
142 | ||||
\( \Downarrow \) | ||||
280 |