People trying to defend philosophy often point out that the natural sciences (
nice question! hard to predict of course ... but some might say that psychology and now cognitive science have partly grown out of 'philosophy' fairly recently ... and some would argue that philosophy is essential for the continued development of cognitive science .... but more importantly (and perhaps you're sensitive to his), one might probably make the case for the value of philosophy intrinsically, i.e. philosophy is valuable in itself, not (merely) in terms of what other (good) things it might produce -- after all, the 'creation' of new disciplines, even if it can legitimately be assigned to philosophy, is a relatively rare thing -- and hard to justify centuries of philosophizing by saying every half a millennium or so it sloughs off a new discipline .... So better to look for your defense of philosophy elsewhere!
hope that's useful ... great question!