| |
| | Goldblatt. Topoi: The Categorial Analysis of Logic (Site not responding. Last check: 2007-10-22) |
 | | These categories are examples of preorders: categories in which there is at most one arrow between any two objects (identity corresponds to reflexivity and composition corresponds to transitivity). |
 | | A category is complete if it has all limits, co-complete if it has all colimits, bi-complete if it is complete and co-complete, finitely complete if it has all finite limits, finitely co-complete if it has all finite colimits, and finitely bi-complete if it is finitely complete and finitely co-complete. |
 | | For Cartesian closed categories, we have 0xA is initial for all A, an arrow A->0 implies A is initial, we can only have a zero object if the category is degenerate (all objects are isomorphic), any arrow 0->A is monic, A^1 is isomorphic to A, A^0 and 1^A are terminal. |
| www.andrew.cmu.edu /~cebrown/notes/goldblatt.html (7165 words) |
|