ABSTRACT
We can see at once that his concept of existence is too narrow. For much of what exists cannot be perceived; for example, a past and a future, an empty space, any kind of deprivation, a possibility, an impossibility, and so on.43 It is not surprising, therefore, that Sigwart himself makes an effort to widen his concept. But what he does is very difficult for me to understand. First, he seems to say that, in order for a thing to be counted as existing, the thing need not be capable of being perceived by me; it is necessary only that it be capable of being perceived by someone or other. At least this seems to be what he means when, after saying that existence is an agreement between the thing thought about and a possible perception, he goes on to say: “That which exists bears this relation not only to me but also to everything else that has being.” Surely Sigwart does not mean to say that everything that there is has the capability of perceiving everything. Perhaps he means only that everything that exists stands in the relation of existence to every other being, in which case his empty-sounding phrase might be taken to say that existence expresses the
capability of acting and being acted upon. (Thus he tells us that “what exists…stands in causal relations to the rest of the world”, and, in a footnote on page 91, that the existent is that which “can exercise effects upon me and others”.) Finally, however, there is some ground for supposing that what Sigwart wants to say is something like this: the existent is that which can be perceived or that which can be inferred as capable of being perceived. For he adds that “in consequence” [i.e., in consequence of this causal relation] “a merely inferred existence may be ascribed to that which is capable of being perceived”.
