Eos had noticed, during his consideration, that the trade as offered had two options, and the two options exhausted the answer space the Painter had built into the question.
The Painter had assumed that Eos would either surrender the branch or accept the loss. The Painter had not built into the question a space for I will not answer the question.
It was quite simple, really. If Eos were given a choice to choose between swallowing poison or stabbing himself, in the guise that this was his only option, then he was going to pick a third option and simply refuse.
It was a clever trick played by the Painter; its silence was a weapon, and if Eos had been careless, then he would not have realized that the Painter had not made any stipulation even when its hand was up, leaving the mind of Eos to work out its intent.
Eos did not get to this point by dancing to the beat of the drum played by his enemies.
