Abstract
Wittgenstein's critique of solipsism is explained as a development in three stages. In the first, which appeares in the Notebooks 1914-16 and Tractatus Logico-Philosophicus, he criticizes the solipsist for not identifying his ego and, therefore, leaving the objects presented to it unidentified. He argues that this is like trying to identify the eye without using any psychological facts. In the second stage, which appeares in The Blue Book and Notes for Lectures on "Private Experience" and "Sensations", he assumes that the solipsist does not even try to identify his ego but merely points at the objects of which he is directly aware. The critique of this inward pointing is based on a development of the original analogy between ego and eye. The third stage is the argument against the possibility of a sensation-language without any connections with the physical world. This appeares in Notes for Lectures on "Private Experience" and "Sense Data" and in Philosophical Investigations. Here the focus is not on the ego but on the objects presented to it. However the criticism is similar: those objects and their types need criteria of identity but would not have sense i f they were not connected with the physical world.