In the preface to the Tractatus Wittgenstein acknowledged 'Frege's great works' as one of the two primary stimulations for his thoughts. Throughout his life he admired Frege both as a great thinker and as a great stylist. This much is indisputable. What is disputable is how he viewed his own philosophical work in relation to Frege's and, equally, how we should view his work in this respect. Some followers of Frege are inclined to think that Wittgenstein's work builds on or complements that of Frege. If that were true it would be plausible to suppose that the joint legacy of these two great philosophers can provide a coherent foundation for our own endeavours. But it is debatable whether their fundamental ideas can be synthesized thus. The philosophy of Wittgenstein, both early and late, is propounded to a very large extent in opposition to Frege's. They can no more be mixed than oil and water—or so I shall argue.
Frege's logical works did indeed stimulate the young Wittgenstein's thoughts. His formalization of the propositional and predicate calculi was the most momentous advance in formal logic since Aristotle. In many ways it, together with Russell's and Whitehead's Principia, set the agenda for twentieth-century philosophy of logic and for modern philosophical reflection on the relation between logical calculi, thought, and language. For, given the power of the new calculus of logic to formalize arguments that had been beyond the scope of previous systems of logic and to display their validity (or invalidity), the moot philosophical question was: what does the new logic signify? What does it show us about the nature of thought, or of language, or of the world?
Frege argued that his new logic freed thought 'from that which only the nature of the linguistic means of expression attaches to it' (BS, Preface). For,