Our species has evolved a curious form of opportunistic altruism, in short the notion that we benefit by caring for one another, while each individual strives insofar as possible to enhance his or her own social status, personal security, wealth and power. Thus much political debate concerns the dichotomy between the common good and individual freedom. Idealism merely represents a set of beliefs in an optimal world, where individuals attain the greatest measure of happiness, satisfaction, affection, personal freedom, physical and material wellbeing. Propagandists like to pepper their speech with frequent references both to our aspirations and to the political ideals dear to our culture or doctrinal system. In much of the world today we have been conditioned to view abstract concepts such as democracy, freedom, antiracism, tolerance, crime-prevention, material wealth as ideals worth fighting for, often with scant regard to their feasibility and the immense contradictions and conflicts of interest that their rigorous enforcement may engender.
An idealist may simultaneously advocate greater economic growth, campaign for a cleaner environment and welcome migration from poorer to wealthier regions, as we all want to enjoy a higher material standard of living, surrounded by uncontaminated, but tamed wildlife and extending such privileges to an ever greater number of world citizens. An idealist can espouse tolerance for diverse lifestyles and intolerance for all kinds of prejudice, without considering whether one's lifestyle conflicts with rights and freedom of others.
Empiricism relies on the morally neutral application of the scientific method. Only ethics tell us that actions such as planting an incendiary device outside a busy restaurant or firing missiles at densely populated neighbourhoods from helicopter gunships are wrong. An empiricist is interested only in establishing the facts and in understanding the motivations of the perpetrators. An empiricist may want to estimate the Earth's long-term human carrying capacity, within verifiable physical technological restraints, regardless of the millions who may die if it proves significantly lower than world's current population. An empiricist may seek to establish whether cold fusion is both technically viable and safe irrespective of any ideological preconceptions or rigid interpretation of the theory of thermodynamics. More important an empiricist can change her or his view on the basis of new scientific data. For instance, if one could prove global oil reserves could last another 300 years without any adverse climate and/or ecological effects, one may need to revise one's view on sustainability of our current petroleum-driven economic model and seek alternative explanations for conflicts over oil supplies.