Carved out of an ideology of secularism is projected the meaning of happiness as that which is affiliated with materiality. It is propagated that only by the fulfillment of man’s concupiscence, through consumption, and his irascibility, through thoughtless reaction, can one satisfy themselves to be entranced in some form of happiness. Truthfully, however, one only ends up satisfying their ‘self,’ not the higher dimension of the soul through intellection, but its lower dimension through carnality. It is a happiness that is temporal and finite. It has no value but an extrinsic value measured by external material factors, which fluctuate with the vicissitudes of time, rising and falling with the tide, emerging and dissipating without any real worth. 
Here is the essential truth of it. If happiness is measured by money, property, goods, things, careers, jobs, ranks and positions, then these are all external entities, and you will thus have given happiness an extrinsic value, as the sacrilegious have. For true contentment is intrinsic, not extrinsic. It cannot be measured by any object of this world, however valuable that object might be. It is of that garb whose cloth is not sown by the threads of carnality and worldly pleasure. This you must understand, and Ghazzālī’s Alchemy is designed to facilitate that understanding.