 This then raises the following pressing question: if, as he argues, intuition is itself a synthetic activity, what “matter” does it synthesize, if not the sensible manifold? Natorp is distressingly elusive on this point, even in his explicit discussions of the status of time and space in science (cf. Natorp 1910c: Chapter 7). The following is clear, however. Like Kant, Natorp understands thinking always to be thinking an object. For Natorp, however, this means “constituting”, “constructing”, or “objectivating” the object. But since he (re)interprets these objects as non-sensible phenomena, he also interprets space and time non-psychologically, i.e., as non-sensible. They are not the forms of sensible intuition, but the ideal system of dimensions (three spatial dimensions plus time (cf. Natorp 1910c: 303, ff.; 397–398), conceived as 