Susan wrote:

Why is yogurt with live acidopilus and bifidus cultures kosher to eat if we are not allowed to eat bugs?

David Preiss wrote:

Why does the Torah speak of forms of life that are visible only to the human eye?

Dear Susan & David,

Good question. Now let me ask you one: Why are we allowed to breathe? Zillions of microorganisms are floating around in the air, and we swallow some with every breath.

The answer is: The Torah prohibits only bugs which can be seen by the naked eye. Organisms seen only with the aid of a microscope are kosher.

The logic is this: The Torah was given to human beings, not angels. Its laws are geared to normal human experience. Bugs we see in 'real life' are forbidden. 'Invisible' ones - which seem like they exist only in a laboratory - are not forbidden.

When improved microscopes brought improved awareness of microscopic organisms, some people suggested that perhaps we should filter our water to avoid consuming the organisms. A renowned rabbi responded: "If you give a nickel to charity while holding it under a magnifying glass, do you get credit as though you gave a dime?"

Speaking of germs: Three amoebae are sitting on a park bench. Suddenly, one of them jumps up and runs off.

"Hey! Where did Harry go?" one asks the other.

"Guess he had to split." (Thanks to E.C.S.)

• Aruch Hashulchan, Yoreh De'ah 84:36