Relationship - For X and Y to be in a relationship, they must be variables, not constants, and they must have codependency, not independence.

Variable X simply being before effect Y is not sufficient for X to be considered a cause of Y and a failure to recognize this fact can lead to the post hoc, ergo propter hoc fallacy. For example, if one suspects that hot temperatures are a cause of sweating, hot temperatures must have been present before the onset of sweating for it to be considered a cause, not after.

Time precedence - Time precedence refers to the notion that for something to be considered a cause, the cause must have occurred before the effect.

In science, three commonly accepted conditions for establishing a causal relationship are time precedence, relationship, and non-spuriousness.

Causal inference is often very important in statistical data, as you are taking a large pre-existing dataset to come to a conclusion, and not a controlled test environment. Some people seem to forget about the part where the data has to support a causal relationship and not just a correlation between the data points. This is central to most of science, and it is literally science at its core. Causality in science Р”В¬ausal inference is the process in which someone can use data to claim there is a causal relationship. For things going slower than the speed of light, such a reversal is impossible unless one gets sucked into a black hole. In physics, the spacetime interval is what defines the flow of causality and reversing its direction causes the direction of causality to be reversed. In more modern times, the discovery that time is relative has had profound implications for the understanding of causality. He would also formulate the problem of induction when he noted that 'our reason fails us in the discovery of the ultimate connexion of causes and effects' as it is 'impossible for us to satisfy ourselves by our reason, why we shouРІР‚в„ўd extend that experience beyond those particular instances, which have fallen under our observation.' Instead he concluded that humans were able to induce cause-and-effect relationships through careful observation of contiguity, succession, and constant conjunction. Of the Idea of necessary Connexion Part II by David Hume Р”В«ut as skeptical as he was, Hume did not believe causal relationships were beyond rational comprehension.

And as we can have no idea of any thing which never appeared to our outward sense or inward sentiment, the necessary conclusion seems to be that we have no idea of connexion or power at all, and that these words are absolutely, without any meaning, when employed either in philosophical reasonings or common life. They seem conjoined, but never connected. One event follows another but we never can observe any tie between them. It appears that, in single instances of the operation of bodies, we never can, by our utmost scrutiny, discover any thing but one event following another, without being able to comprehend any force or power by which the cause operates, or any connexion between it and its supposed effectРІР‚В¦ All events seem entirely loose and separate. РІР‚Сљ РІР‚СњWe have sought in vain for an idea of power or necessary connexion in all the sources from which we could suppose it to be derived. He called into question the very ability of the human mind to understand it. David Hume was chief among the philosophers to challenge the nature of causality promoted by the Ancient Greeks, Aquinas, and Aquinas's scholastic colleagues. Wes Morriston is hardly the only skeptic when it comes to causality. The philosopher Wes Morriston offers a detailed counterargument in his paper Must the beginning of the universe have a personal cause? where he argues that 'when applied to the beginning of time, the principle that whatever begins to exist must have a cause is not clearly true.'

Whether universal causality is true is debatable. Both Aquinas's argument and the Kalam cosmological argument expand upon Plato's belief that everything has a cause which is a philosophical position called universal causality. Thomas Aquinas later argued that 'from every effect the existence of the cause can be clearly demonstrated, and so we can demonstrate the existence of God from His effects' and the Kalam cosmological argument uses a similar line of reasoning. Aristotle expanded upon Plato's idea of causality in Physics and Metaphysics where he argued that there were four causes, namely the material, formal, efficient, and final cause.

Reverse causality example