From the Cut n Paste
人们以为蝙蝠,甲虫,鼠及猫头鹰都是夜间活动,必定是盲的。。。其实不然。可是,这样的假定就使我们比喻盲目的,或视力有困难者为 “Blind as a bat/ A beetle/ A mole/ An owl了。”
Example
People assume that because bats, beetles, moles and owls are active in the dark they must be blind...which they aren't. That assumption, though, has led to our saying that anyone who is blind or who has difficulty in seeing is blind as a bat/ a bettle/ a mole or an owl. " Without my glasses I'm blind as a bat."
For me
For me