user6953: Suppose A's granddad died many years ago and was buried in the back yard.
Right next to his tomb, grows a very fruitful apple tree. There are many delicious apples on that tree.
Is it ok to eat these apples?
There is a very high chance, that the tree obtained energy from the tomb. When the granddad's corpse decayed, it released a lot of biological substances that are good for the tree.

user5191: Yes.                   It is ok.

6953: <p>Suppose A's granddad died many years ago and was buried in the back yard.</p>

<p>Right next to his tomb, grows a very fruitful apple tree. There are many delicious apples on that tree.</p>

<p>Is it ok to eat these apples?</p>

<p>There is a very high chance, that the tree obtained energy from the tomb. When the granddad's corpse decayed, it released a lot of biological substances that are good for the tree.</p>
 5191: <p>Yes.                   It is ok.</p>
