1 | 3. a: q*. a E a 4. a,b: q*. (a E b)  (b E a) 5. a,b,c: q*. (a E b)  (b E c)  (a E c) 6. x,y: q*. Dec(x E y) 7. f: q*   8. g:    q* 9. g o f = Id 10. f o g = Id 11. a:  (g(a)) E (g(a)) |
2 | 3. a: q*. a E a 4. a,b: q*. (a E b)  (b E a) 5. a,b,c: q*. (a E b)  (b E c)  (a E c) 6. x,y: q*. Dec(x E y) 7. f: q*   8. g:    q* 9. g o f = Id 10. f o g = Id 11. a:  12. b:  13. (g(a)) E (g(b)) (g(b)) E (g(a)) |
3 | 3. a: q*. a E a 4. a,b: q*. (a E b)  (b E a) 5. a,b,c: q*. (a E b)  (b E c)  (a E c) 6. x,y: q*. Dec(x E y) 7. f: q*   8. g:    q* 9. g o f = Id 10. f o g = Id 11. a:  12. b:  13. c:  14. (g(a)) E (g(b)) 15. (g(b)) E (g(c)) (g(a)) E (g(c)) |