The bear needs the mouse. The mouse does not need the bear. If something needs the bear then the bear does not eat the mouse. If the bear likes the mouse then the bear needs the mouse. If something needs the bear and it is cold then it does not like the bear. If something likes the mouse then the mouse likes the bear. If something is big and it does not like the bear then the bear eats the mouse. If something does not like the bear and the bear does not eat the mouse then the bear needs the mouse.
The mouse needs the bear.