Glad to be alive: How we can compare a person's existence and her non-existence in terms of what is better or worse for this person

This paper defends the claim that if a person P exists, there can be true positive comparisons between P's existence and P's never having existed at all in terms of what is better or worse for P. If correct, this view will have significant implications for various fundamental issues in population ethics. I try to show how arguments to the contrary fail to take note of a general ambiguity in comparisons when compared alternatives contain their own different standards (or, in the case of non-existence, a lack thereof) on which to base these comparisons. After having answered arguments against the possibility of making positive comparisons, the paper develops a positive account of how to make existence/non-existence comparisons in terms of personal value whilst accepting that a person's non-existence fails to make any contact with the relevant categories of personal value. The guiding idea is the following: When some item satisfies some relevant standard, we can, I argue, infer that it satisfies this standard better than something that fails to satisfy this standard (be this failure due to empirical or conceptual reasons).