This chapter considers Swift’s uses of philosophy – his use of the word, and the uses to which philosophy can be put, good and (mostly) bad. It looks at Swift’s uses of the term ‘philosophy’, its cognates, and some related terms (‘speculative’), and at his references to philosophers, to suggest he can use the term in a restricted positive sense as well as a more definitively negative sense, particularly in A Tale of a Tub, where hubristic claims towards systematic description characterise philosophical speculation allied with natural philosophy. The chapter concludes with a reading of Gulliver’s Travels, suggesting that Swift’s capacity for fable and invention enabled him to practise a literary philosophy.