A good way to know that this is bullshit is 1) controlled studies show that homeopathy fails to outperform placebo , 2) it contradicts vast swaths of physics, chemistry, biology, and medicine (and you know those sciences work because they cure our infections and give us computers), and 3) evidence clearly shows that the central tenets of homeopathy – for example, that like cures like and dilution increases potency – are just plain wrong . Belief in homeopathy appears to be driven by expectancy effects and the placebo effect .