We have always known Samuel Pepys liked the occasional bit of nooky with a prostitute in an alley off Fleet Street, on his way home to his wife Elizabeth in Seething Lane.

But if like me you have always brushed off that behaviour as 'that was just how things were in the 1660s, and I don't think he did it too often', it is time to think again.

Unfortunately, as a new edition of his famous diaries illustrates all too vividly, we now have to add Pepys to the list of formerly respected famous figures who turn out to have fallen catastrophically short of acceptable sexual behaviour, to the point where their names are now mud.

Most of us treasure Pepys as an essentially sound family-minded man, who buried his Parmesan during the Great Fire of London, made merry music round his table in the evenings, picked 'sparagus' from his garden, and sat up in bed late into the night talking and bickering with his dear wife.

His diaries are close to our hearts because they give us a uniquely detailed glimpse into how one man's daily life was lived in those days: boats up and down the Thames, busy days in the Naval Office, fretting about over-expenditure on his wife's clothes, a hearty supper, and so to bed.