Questions with the keyword 'visual'

• why do we have eyes? and not use some other method by diamondpwh to Helen, Jenni, Mark, Martin, Stu Comments: (No comments so far )
• Why is it that when you stare at something for too long, two images merge together, so you see two different things? by mennie13 to Helen, Jenni, Mark, Martin, Stu Comments: (No comments so far )