Weak Pullbacks
A weak pullback of a cospan X → Z ← Y is a cone over the cospan that is only weakly universal, that is, the mediating morphism u : Q → P above need not be unique.
Read more about this topic: Pullback (category Theory)
Famous quotes containing the word weak:
“If you set to work to believe everything, you will tire out the believing-muscles of your mind, and then you’ll be so weak you won’t be able to believe the simplest true things.”
—Lewis Carroll [Charles Lutwidge Dodgson] (1832–1898)