The action in which those attending a celebration clink glasses with each other has a somewhat sinister origin.

In ancient times one of the surest and most discreet ways of killing an enemy or rival was though poisoning. Therefore, one was never sure when it would be its last drink.  

Hosts in order to clear up any doubts and reassure the guests, clinked their glasses with their guests so that the liquids passed from one glass to the other, by doing so everyone drank partly the same thing.

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A much more beautiful origin of toasting is that drinking wine involves all the senses except hearing... By clicking the crystal glasses together, we can enjoy all our five senses.

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