A default philosophy is a system of philosophy that claim to do no more than describe things as they are rather than offer a system that offers an alteration of our perception of the world by eliminating concepts which are ordinary in human discourse or add concepts noone before had thought necessary. Such philosophies can serve as defaults in the sense that they are the ones that can be gone back to as reliable and basic when philosophies with an ax to grind, a point of view to expound so as to create a new vision of the metaphysical universe, one not previously crafted. Aristotle and, I think, David Hume, and perhaps Kant, are of that first kind in that they offer a bottom line of accurate description without the intrusion of their own special views, while Spinoza is a philosopher of the second kind in that he finds no need, in his very comprehensive philosophy, ever to invoke the concept of justice, and therefore shows how you can account for the world without it, which is as much as to say that there is no such thing as justice. Freud, if he is to be considered among the ranks of philosophers, does his work by including a new concept, that of the unconscious, as necessary for the understanding of human life, and the bulk of his work is to show that this uncharted territory is not only there but how it works. Twentieth Century eliminators, as they might be called, include Gilbert Ryle, who says, contrary to all sense, that there is no such thing as subjectivity, and Wittgenstein, who gets rid of thinking that much of speech is about propositions, however much that may impoverish or, depending on your viewpoint, liberate language.