A micro-simulation is described, for rational and irrational strategies\nin human mating behaviour. The spread of irrational behaviour through\na population from a single initial individual, the `contagionist\nparadigm', is shown to be highly unlikely in most realistic circumstances.\nAn exception to this rule is shown to be where the `self-fulfilling\nprophecy' phenomenon is exhibited, i.e.. the irrational meme affects\nthe outcome of the mating. Additionally, where the irrational strategy,\nunder conditions of self-fulfilling prophecy, is allowed to co-exist\nwith a rational strategy (i.e.. a strategy based on factual information),\nboth can proceed to fixation, resulting in a population of individuals\nexhibiting both rational and irrational memes simultaneously. However,\nwhere successful pairs are removed from the population, there is\na tendency for neither behaviour to persist. Maintenance of either\nbehaviour in the population under circumstances of removal of successful\npairs requires a cultural information system, i.e.. one where a common\npool of information may be accessed without a requirement for contagion.\nThis implies that contagionist explanations of culture may be strictly\nlimited in their application. Some attempt is then made to generalise\nthe conclusions to financial systems.