""There may be in the cup / A spider steeped, and one may drink, depart, / And yet partake no venom, for his knowledge / Is not infected: but if one present / Th' abhorred ingredient to his eye, make known / How he hath drunk, he cracks his gorge, his sides, / With violent hefts. I have drunk, and seen the spider.""

Источник: The Winter`s Tale

"...there is nothing either good or bad, but thinking makes it so."

Источник: Hamlet