Question

writing with a purpose
from the declaration: . . . a decent respect to the opinions of mankind requires
that they should declare the causes which impel them to the separation. ¹

how does this part of the introduction use ethos?
type answer here...

Explanation:

Ethos is about establishing credibility/ethical appeal. The phrase "a decent respect to the opinions of mankind" shows the authors (of the Declaration) respect public opinion, implying they act with moral responsibility. By stating they should declare their causes, they present themselves as reasonable, ethical, and worthy of trust, as they follow the norm of justifying their actions to humanity.

Answer:

This part uses ethos by emphasizing a "decent respect to the opinions of mankind" to establish the authors’ ethical credibility: it shows they recognize the moral obligation to justify their separation (by declaring its causes) to humanity, portraying themselves as reasonable and morally responsible, thus gaining the audience’s trust.