This might not be appropriate for the 101 section, but this is my two cents on Stirner and human nature:
According to philosophers from Plato to Hegel, human nature is defined by the capacity for rational thought or reason, while physical activity and toil are typically relegated to the lowly realm of animality. Against this idealist tradition, a Young Hegelian upstart named Ludwig Feuerbach contended that the essence of human nature consisted in community, arguing that human nature or “species-being” existed through individuals’ consciousness of themselves as part of a common species or human community, which in his view implied everyone should get together in a big love-fest for their fellow humans and worship “Man”. This provoked Stirner’s scathing critique of human nature/'Man', which for him was merely an abstract concept serving to conceal and repress the real uniqueness of individuals. By positing human nature as a fixed essence or set of attributes, Stirner argued in proto-existentialist fashion, Feuerbach established an exclusionary and oppressive norm which denied the individual’s capacity to freely create him- or herself. Like God, “Man” was essentially a religious illusion demanding the same obedience and self-sacrifice. Meanwhile the young Marx, then well-known as a Feuerbach groupie, defined human nature/species-being as co-operation in production, that is, labour or work. With a big slap to the philosophical tradition, Marx argued that human essence is defined by the mundane everyday activity and relations of production. Animals may “work” to sustain and reproduce themselves, but their activity is purely instinctual, whereas human work is conscious and planned. In his view, humans are especially distinguished from animals by the fact they produce their own means of production, thus creating and modifying their own needs, beyond the mere animal needs for food, water, sex. So Marx’s account of a universal or essential human nature accounts for the variation and development of particular human needs, desires, characteristics etc. manifested in different historical epochs according to the level of production and other circumstances. Furthermore, the relations of production denoted by Marx’s concept of human essence/Man are a *material* reality determining/conditioning what individuals can be or make of themselves. In other words, they are not merely imaginary “spooks” or “wheels in the head” that can be dissolved by an act of individual will in the style of Stirner.