"Throwing the baby out with the bath water" is an expression that implies that an entire idea, concept, practice or project doesn't need to be rejected or discontinued if part of it is good. The baby, in this sense, represents the good part that can be preserved. The bath water, on the other hand, usually is dirty after the baby is washed and needs to be discarded, just like the parts of the concept that are bad or useless.
Origins of the Phrase
There are many ideas on the possible origins of this expression. Many people incorrectly attribute the expression to English or Irish origin. The phrase was first recorded in 1512, and used by a German writer, Thomas Murner, in his verse book, Die Narrenbeschworung. From Germany, the expression became commonly used in the United Kingdom and then in France.
The idea of throwing the baby out with the bath water might be inspired by the relatively few baths taken by people in Europe before the 16th century. Baths were often thought to be unhealthy, and they were difficult to prepare, because the bath water had to be drawn and heated. The difficulty of preparing bath water often meant that the same water might be used for a whole family’s bath, and the baby was frequently bathed last. At this point, the bath water might be quite dirty and might obscure view of the baby. A mother wouldn’t want to mistakenly discard the baby with the dirty, murky water — not that this was likely to occur.
The Good and the Bad
Throwing the baby out with the bath water isn’t likely to occur, but the expression of it has been a metaphor for the dichotomy existing in an idea or practice that is both good and bad. In such cases, the good can be kept while still getting rid of the bad. Some people might be inclined to get rid of everything and start over, and this expression is often used by people to encourage the preservation of the good parts.
Expresses an Opinion
The expression can be highly subjective, because individuals might define what constitutes good and bad in very different ways. Someone who disapproves of human cloning, for instance, might feel that other types of cloning also are bad and that all attempts at cloning should be rejected. Another person who disagrees with human cloning but supports research into other types of cloning might say that rejecting all types of cloning is akin to throwing the baby out with the bath water.
This phrase points out a logical fallacy. The assumption is that if something is bad and it belongs to a group, then everything in that group must be bad. A related expression might be that “one bad apple spoils the bunch.” When applied to this example, the phrase would express the idea that discarding all of the apples would waste any good apples that were in the bunch.
Legal Applications
In some cases, it is necessary for a system to practice throwing the baby out with the bath water. In some criminal justice systems, for example, an illegally obtained confession or an illegal search can mean that any evidence resulting from these is not admissible. This is often referred to as “fruit of the poisoned tree.” Under certain laws, any evidence arising from a violation of the justice system is considered tainted and cannot be used.