  The notion of a self-evident proposition is a term of art in intuitionist thought, and needs to be distinguished from certain common sense understandings with which it may easily be conflated. The first thing to note is that a self-evident proposition is not the same as an obvious truth. To begin with, obviousness is relative to certain individuals or groups. What is obvious to you may not be obvious to me.  But self-evidence is not relative in this way. Although a proposition may be evident to one person but not to another, it could not be self-evident to one person, but not to another. A proposition is just self-evident, not self-evident to someone. Secondly, there are many obvious truths that are not self-evident. Certain well-known empirical truths, for example, that if I drop a heavy object it will fall, or that the world is bigger than a football, are obvious but not self-evident. There are also self-evident propositions that may not be obvious to everyone, at least prior to reflection, e.g., that if all As are Bs and no Bs are Cs then no Cs are As, or that one man can be the father and grandfather of the same child. 