There has been a long discussion about the seemingly large gap between Wittgenstein's early work, the Tractatus Logico Philosophicus (hereafter only TLP) and his posthumously published Philosophical Investigations (hereafter only PI). In this paper I argue that one of the main reasons for Wittgenstein turning away from the view uttered in the TLP was the Colour-Exclusion problem. I try to make clear what exactly the Colour-Exclusion problem is with regard to Wittgenstein's TLP and why it is so important.
The first chapter makes clear what the purpose of the Tractatus is. I point out what Wittgenstein wanted to achieve and give a brief overview of the main theses. The second chapter will focus on the problems of the TLP and serves as a connection to the discussion of the Colour-Exclusion problem in the third chapter. The fourth and last chapter then delivers an insight into the influence the problem had on Wittgenstein's philosophy and methodology.