I realise that this http://www.legislation.gov.uk/ exists,

but it does not help, If one were to want to find out what ones rights were, and to what extent one can challange or change stuff.

Is there somewhere which sets out why individual human beings, should have to do what some words have said, even if there is not contract or agreement from the individual to be bound by those words.

PS Obviously some things can be rationalised (not harming or impeding freedoms of others etc) But much legislation is not obvious about why a human animal should have to comply with, where is the explanation/thinking behind this laid out?