then the response is:

If everything they call a demonstration must contain a universal proposition, that universal proposition must be known—that is, its universality must be known. Otherwise, whenever it is admitted that it might be particular rather than universal, knowledge of what follows from it cannot be attained. An unquantified or unrestricted proposition whose wording permits either a universal or a particular interpretation has the force of a particular proposition.

If the knowledge obtained through the syllogism to which they reserve the name “demonstration” necessarily requires knowledge of a universal affirmative proposition, the response is this: if knowledge of that proposition is self-evident, then knowledge of each particular instance falling under it can, with even greater reason, be self-evident. If it is inferential, it requires self-evident knowledge, leading to intractable circularity or [an infinite regress in mass-transmitted reports] (*), both of which are invalid.

The same applies to all the other universal propositions they make the starting points of demonstration and call “those that must be accepted.” These may be propositions derived from external or internal sensation—the latter being what a person perceives within himself—or propositions based on experience, mass-transmitted reports, or intuition, according to those who count some intuitive propositions among the soul’s apprehensions that must be accepted. An example is knowing that the moon derives its light from the sun by observing how its phases change as its alignment with the sun changes: its appearance when it is close to the sun after conjunction, as on the night of the new crescent, differs from its appearance on the night of opposition, when it is full.

They disagree, however, over whether intuition can yield certainty.

The same applies to purely rational propositions, such as our statements that one is half of two and that the whole is greater than the part