Full Idea
How do I know that other people have minds? The question is a bad one. Precisely because I encounter them at work, play and the like, it is guaranteed that they, too, are Dasein, intelligent agents.
Gist of Idea
If we work and play with other people, they are bound to be 'Dasein', intelligent agents
Source
report of Martin Heidegger (Being and Time [1927], p.153-) by David E. Cooper - Heidegger Ch.3
Book Reference
Cooper,David E.: 'Heidegger' [Claridge 1996], p.31
A Reaction
I've seen film of someone playing peek-a-boo with a bonobo ape, so presumably they have Dasein. It might be easier for the AI community to aim at building a robot with Dasein, than one which was simply conscious.