Drawing conclusions from evidence involves a certain amount of the use of logic. Come to think of it, every statement that purports to express a truth involves logic. But when we look at the normal human tendencies of bias due to our preferences and combine them with a lack of rigorous logic, we have a large number of logical fallacies involved in religious matters.
An old book called The Two Babylons by Alexander Hislop is a good example. Hislop shows that ancient pagan religions used images of a mother and child, then shows that Roman Catholicism uses images of a mother and child. Therefore this is held as support that the Roman church had pagan origins. A similar technique is used by the Jehovah’s Witnesses in their booklet Should You Believe In The Trinity? In this booklet, the Watchtower presents images of ancient cultures and religions that had statues with three heads, and compares this to the trinity, as if the two had some sort of connection. They compare images or surface level similarities and say it is obvious that the two have a common connection.
Well, sorry, but this is not a logical connection, and it is not so obvious. Merely because an ancient culture used images that were simlar to images used in Christianity does not show a causal connection. Further, using phrases such as ‘it is obvious that’ and ‘the reader cannot fail to see’ and ‘many agree that’ are rhetorical techniques that do not present any valid conclusions. The work of Hislop and The Watchtower fail to present valid conclusions in this regard, and end up confusing more than clarifying. We should all be aware of these types of logical fallacies and avoid them.