Ockham's distinction between formal and material consequences shows that substitutional invariance alone cannot demarcate formal validity without prior commitment to a fixed ontology of terms.

?Rate how convincing each reason is below to see the overall strength.

No one has weighed in yet. Be the first to share reasons for or against this statement.

Demarcate(as describing how clearly a numeral can distinguish between different physical states): To clearly mark or separate the boundaries between one thing and another.
Ockham (William of Ockham)(as the originator of the mental language theory being discussed): A medieval philosopher (1287-1347) known for the principle that simple explanations are better than complicated ones, and for developing theories about how language and thought connect to meaning.
Ontology(Carnap argues this enterprise is based on a mistake): The philosophical discipline that tries to answer hard questions about what there really is.
Substitutional invariance(discussed as potentially insufficient for determining formal validity): The idea that a logical rule holds true no matter what terms you swap in and out—if it works with 'cats' and 'animals,' it should work with any other pair of terms following the same pattern.

Based on where you are in your exploration