§67

Wittgenstein suggests that the 'similarities overlapping and criss-crossing' in the case of games are a bit like the similarities between family members. They might not always resemble each other in exactly the same way. A son might have his mother's mouth and his father's hair (his mouth resembles his mother's mouth and his hair resembles his father's hair).

'Game' is a family resemblance concept. Similarly 'number' is a family resemblance concept.

Wittgenstein uses the analogy of a thread made up of fibres. Where there is a resemblance between members of a family (numbers, games, language-games) we might picture this as the fibres coming together in a thread. But there isn't any one fibre that runs through the entire thread. - There are various overlapping similarities (various fibres bounded together in a single thread).

Someone might respond to this that there is in fact something in common throughout all games - the disjunction of all their common properties. (So 'game' could be defined as something entertaining OR competitive OR involving an element of luck OR involving a particular kind of skill).

BUT this response is no more satisfactory than saying 'there is a common element to the whole thread - the continuous overlapping of fibres'.