Full Idea
It is not only oneself that one discovers in the Cogito, but those of others too.
Gist of Idea
We discovers others as well as ourselves in the Cogito
Source
comment on René Descartes (Meditations [1641], §2) by Jean-Paul Sartre - Existentialism and Humanism p.45
Book Reference
Sartre,Jean-Paul: 'Existentialism and Humanism', ed/tr. Mairet,Philip [Methuen 1980], p.45
A Reaction
The analytical tradition requires a bit more than an instant perception of others in oneself. The problem of 'other minds' must at least be mentioned. However, the way to get to know a universal is to fully study a single instance.