Nine people are sitting in the squares of a 3 by 3 grid，one in each square，as shown． Two people are called neighbours if they are sitting in squares that share a side． （People in diagonally adjacent squares，which only have a point in common，are not called neighbours．） Each of the nine people in the grid is either a truth－teller who always tells the truth， or a liar who always lies． Every person in the grid says：＇My neighbours are all liars＇． Given only this information，what are the smallest number and the largest number of people who could be telling the truth？
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Nine people are sitting in the squares of a 3 by 3 grid，one in each square，as shown． Two people are called neighbours if they are sitting in squares that share a side． （People in diagonally adjacent squares，which only have a point in common，are not called neighbours．）
Each of the nine people in the grid is either a truth－teller who always tells the truth， or a liar who always lies．
Every person in the grid says：＇My neighbours are all liars＇．\\
Given only this information，what are the smallest number and the largest number of people who could be telling the truth？