The Cause vs Correlation Pitch

The findings suggest that exposure to cannabis by itself does not lead to depression but that it may be associated with later suicidal thoughts and attempts.

This article argues that the link between income inequality and violent property crime might be spurious, complementing a similar argument [...] by the author on the determinants of homicide. ... [The link] might be spurious [because] income inequality is likely to be strongly correlated with country-specific fixed effects such as cultural differences. A high degree of inequality might be socially undesirable for any number of reasons, but that it causes violent crime is far from proven.

CO2 increases may accompany temperature increases rather than causing them. Indeed, some high resolution studies have suggested that the temperature increases precede the CO2 increases. Interestingly, also, ice core data shows strong temporal correlations between inferred temp. and amount of dust preserved in the ice core. Finally, the older geological record shows several dramatic examples of where CO2 concentration and global average temperature were either unrelated or even anti-correlated.