Quod fieri debet facile præsumitur.
What ought to be done, is easily presumed.
Quod fieri debuit pro facto censetur.
What ought to have been done, is reckoned as done.
Quod fieri non debet factum valet.
What should not be done, is not valid, when done.
Quod fieri vetatur ex directo, vetatur etiam ab obliquo.
What is forbidden to be done directly, is forbidden also indirectly.
Quod fraude factum est in alios infectum esto, contra fraudatorem valet.
Let what is done in fraud, be inefficient towards others; it is valid against the defrauder.