It is an essential part of our social tragedy that people, like farmers, the industrial workers, the medical profession, etc., influence the social process not only by their work, but also and even predominantly by political ideologies. For political activity hampers objective, rational activity; it splits professional organizations into warring ideological groups; it disorganizes the industrial workers: it restricts the work of the physician and harms the patients, etc. In brief, political activity prevents precisely what it pretends to achieve: peace, work, security, international cooperation, objective expression of opinion, freedom of belief, etc.
Now "cybernetics" is the term coined by Wiener to denote "steersmanship" or the science of control. Although current engineering usage restricts it to the study of flows in closed systems, it can be taken in a wider context, as the study of processes interrelating systems with inputs and outputs, and their structural-dynamic structure. It is in this wider sense that "cybernetics" will be used here, to wit, as system-cybernetics, understanding by "system" an ordered whole in relation to its relevant environment (hence one actually or potentially open).
Active liberty is particularly at risk when law restricts speech directly related to the shaping of public opinion, for example, speech that takes place in areas related to politics and policy-making by elected officials. That special risk justifies especially strong pro-speech judicial presumptions. It also justifies careful review whenever the speech in question seeks to shape public opinion, particularly if that opinion in turn will affect the political process and the kind of society in which we live.