[TYPES] [newbie] is {initial, terminal} object the identity for {coproduct, product}?

Larry Evans cppljevans at suddenlink.net
Tue Aug 31 15:22:55 EDT 2010


Define + as the coproduct operator,
  IOW, X+Y is the coproduct of X and Y for some category C.
Define * as the product operator,
  IOW  X*Y is the product of X and Y for some category C.
Define 0 as the initial object of C.
Define 1 as the terminal object of C.

Is it true that, for all objects, X in C:

  X+0 = X
  0+X = X
  X*1 = X
  1*X = X

?  Also, what's X*0 and X+1?

TIA.

-Larry




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