Acquiescence versus laches: active assent contrasted with passive delay, affecting proof of acceptance and waiver. Acquiescence denotes active assent or conduct recognizing and permitting an existing transaction to be carried into effect, implying knowledge and intentional acceptance. Laches denotes passive neglect or undue delay in asserting rights and may be evidence of acquiescence but is not equivalent to it: laches concerns delay after an act is done, while acquiescence concerns conduct during performance or acceptance of an existing state.