And if you're ever forced to question yourself in this way, later you can never forget it - it's always there inside you like a gremlin waiting to pop up. You can never put back exactly as it was your vision of what there was or what you are - nearly, maybe, but not entirely. After that there's always the crack in the golden bowl, or, as Leontes says,
There may be in the cup
A spider steep'd, and one may drink, depart,
And yet partake no venom ( for his knowledge
Is not infected): but if one present
The abhorr'd 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.
By their last confrontation, if not before, Jack has seen the spider.