It is of course possible to identify as elements of a system all the moments of the Meditation; the test of the doubt for the perceptions received from the senses and the tests of dreaming and sleeping may all be re read from the inside of the system when it is laid out, in so far as they are positive tests which the subject who is slowly becoming qualified as a subject of certainty did indeed pass through; what the system will have to say about the foundations of sensible certainty, about the divine guarantee, about the functioning of the senses will then come to coincide with that which is revealed in the meditation test.