Paul Grice proposed the following conversational maxims in "Logic and Conversation":
The maxim of quality, where one tries to be truthful, and does not give information that is false or that is not supported by evidence. According to the first rule – people are expected to say what they know to be true. When talking with each other – we expect people to tell us the truth. Lui Tuck Yew telling us that public transportation is subsidised is stretching it a bit. How can SMRT be subsidised when the CEO is paid more than Barack Obama, the U.S. President who can rightfully boast: Osama is dead, GM is alive?
The maxim of quantity, where one tries to be as informative as one possibly can, and gives as much information as is needed, and no more. According to this rule – when talking, people are expected to provide just enough information to get their point across. It is fruitless to quote 35,000 private homes are still under construction, 45,000 units are in the pipeline, plus 17 private residential plots which developers can build 8,100 units, when it is still a myth $100,000 flats are affordable for individuals earning $1,000 a month.
The maxim of relation, where one tries to be relevant, and says things that are pertinent to the discussion. According to this rule – you are expected to stay on the topic. In other words, make sure that your comments fit with what is being talked about - make sure your comments are relevant. Sure, the guy can quote lots of people who got caught for speeding and are not sent to jail, but how many colluded with their staff to deceive the authorities?
The maxim of manner, when one tries to be as clear, as brief, and as orderly as one can in what one says, and where one avoids obscurity and ambiguity. This last rule states that your comments should be direct, clear, and to the point. You should avoid using vague or ambiguous language when speaking. Promises of hope, home and heart are too nebulous when COE breaches $100,000 (no hope), HDB flats go for a million (no home), Medisave minimum sum raised to $38,500 (no heart).
Still interested in talking? Go for your life.
[Historical aside: Differing views and solutions to national policy were encouraged during Mao Zedong's Hundred Flowers Movement (Chinese: 百花运动 ) of 1956. Soon after, he abruptly changed course and acted against those who were critical of the regime and its ideology. Mao remarked at the time that he had "enticed the snakes out of their caves."]