I don't understand this sentence. It is very grateful if anyone can clarify it.
"Understanding presupposes ability to attract and sustain otherís attention."
"For understanding, it is necessary that one is able to attract another person's attention, and to sustain (keep) their attention."
It sounds wrong, because understanding something actually requires the reverse - the ability to attend to something and concentrate on it.
Perhaps it is supposed to mean, "[For one] to be understood presupposes the/an ability to attract and sustain others' attention."