Single Idea 3624

[catalogued under 11. Knowledge Aims / B. Certain Knowledge / 5. Cogito Critique]

Full Idea

From the fact that I am thinking it follows that I exist, since that which thinks is not nothing. But when he adds 'that is, I am a mind, or intelligence, or intellect', a doubt arises. ..You might as well say 'I am walking, therefore I am a walk'.

Gist of Idea

That I perform an activity (thinking) doesn't prove what type of thing I am

Source

comment on René Descartes (Meditations [1641], §2.26) by Thomas Hobbes - Objections to 'Meditations' (Third) 172

Book Reference

Descartes,René: 'Meditations on First Philosophy etc.', ed/tr. Cottingham,John [CUP 1986], p.70