Dr Mahathir is a scientist, so he really ought to understand that the successes of the modern world ultimately rely upon a civilised decision by educated folk not to fight over every disagreement.

That includes the abuse of the law as a weapon to brow beat your enemies and waste your own time and energy in the process.

Tommy Thomas has arrived at an opinion about the May riots and he has expressed it. The sensible and mature way to manage any disagreement one might have is to express your contrary opinion (in the same measured and polite tones that Mr Thomas himself used) and lay out what you believe are the facts to support your view that his analysis was wrong or unfair.

Setting up sacred cows of the past or present, which can never be questioned or criticised and for which every generation must show greater veneration than the last, until forced worship and deification ensues, is to the contrary a sure way to put a lid on progress and trap a society in a medieval darkness of the mind.

Fighting, hysteria and blind faith in the irrational soon follows.

Time and again, progressive societies have reviewed and revised prevailing opinions on history, science and the rest.  By such means, for example, the British have reconsidered many former heroes in the light of more progressive values or the discovery of matters previously unknown. The weaknesses are acknowledged together with the strengths. Why worship blindly?

Indeed, a refusal to accept the slightest criticism of past figures smacks of a present agenda by those seeking to profit by association. The path to constant progress on the other hand is a calm, open-minded thoughtfulness that remains humble in its conclusions (the proud never learn).

Quite apart from the above, you cannot libel the dead so Dr Mahathir had best get over it.