A Scottishclan is a Scottish family which (usually but not always) has its own tartan[?]. Most clans in Scotland didn't get on. Also note that some tartans[?] don't come from clans but from regiments-for example Black Watch[?]. As names change a lot of clans go by more than one name-MacCutcheon is the same clan as MacDonald for instance. Also one family name may have more than one clan.
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The placebo effect. Medicines or treatments, known to have no effect on a disease, can have major effects on a person's perception of ...