-By conception I mean the substantivation of to conceive which is somewhat problematic because to conceive is nearer to to think. In Germanic languages it is the substantivation of begreifen (substantivised as Begriff, in Dutch begrip) which if translated in English is nothing but to understand.
-Perception is nothing but the substantivation of to perceive. Everybody knows what it means: it is nothing but letting our senses do their job. In science it is (unfortunately) reduced to observation. In other words, it is by definition 'a posteriori'.
-Ontology stands for one of the components of metaphysics as a system.
-In science everybody knows that it is based on perception or observation. However, conception (putting aside the linguistic problem mentioned above) is innate (see the Kantian 'a priori').
-So, my question could be translated as: Is the 'a priori' ontologically earlier than the 'a posteriori'?
-Please check whether my logic is right. Thanks for your answers. Marc.