This section surveys arguments for haecceitism. The most familiar of these are conceivability arguments, which appeal to the apparent conceivability or imaginability of maximal possibilities that differ haecceitistically. Another line of defense takes the form of an argument usually called “Chisholm’s Paradox”, which exploits incremental modal variations in order to defend haecceitistic differences. In addition, one might endorse haecceitism, not on the strength of any distinctive argument, but by a more general appeal to modal intuition, according to which haecceitistic differences simply seem possible. This survey of arguments leaves aside the general issues in modal epistemology raised by appeals to modal intuition, focusing instead on conceivability arguments for haecceitism and Chisholm’s Paradox.