What is the difference between cause and reason?

Question

I noticed that Spinoza (Ethics, proof for Prop. XI) mentions cause and reason often in the same sentence, but what is the actual difference between these terms?

Example:

"If, then, no cause or reason can be given, which prevents the existence of God, or which destroys his existence, we must certainly conclude that he necessarily does exist."

I always thought these words are synonyms, but now, when tried to find something about it in the internet, it seems that reason should mean something more mental, so cause is not mental? Or perhaps it depends who is causing it, in this example given is it then reason something what God is causing , and cause would be external, then?

Answer 1

Such is the "principle of sufficient reason" and "...many philosophers of the period...did not carefully distinguish between the two."

Per https://plato.stanford.edu/entries/sufficient-reason/#Spin we can see how Spinoza uses the terms interchangeably: "Nothing exists of which it cannot be asked, what is the cause (or reason) [causa (sive ratio)], why it exists." A translation of "causa (sive ratio)" is either "the cause (or cause)" or "the cause (or reason)", even "the cause (or system)". Related to "ratio" note also that "rati" and "ratus" translate to "thinking" (compare to cogitare) - as well as by some accounts "thoughtlessly".

The terms are, however, either synonymous or antonymous depending on use of term. For example,

Q1: "Why are you shivering?" &
Q2: "Why are you putting on your sweater?"

are both answered by

A: "Because I am cold"

In the former instance, the answer cites (brute, physical, non-volitional) cause, in the latter, reason (and arguably, volition or "logical cause"). To discern meaning and intention with use of term, you might appreciate Grice's, "Utterer's Meaning and Intention." Lastly, as for how the "mental" is causal, you might want to investigate intentionality and I would recommend Searle's "Intentionality".

Answer 2

There are three definitions of reason according to MW. If we are talking mental life, all reasons (MW) given by an agent are causes (presuming mental causation (SEP), of course), but not all causes (SEP) are reasons. But we must use the correct definition of reason, as there are three at least. From MW, we see from the second definition:

reason₂: something (as a belief) that serves as the basis for another thing

Thus, when we act on our beliefs, our beliefs or reasons₂ are the causes of action. But many causes in the world are not part of our mental life. For instance, if a virus causes us to develop diabetes, while we may ask for a reason, in this sense we are talking reason₁ where we are merely seeking an explanation, in this case provided by a virologist on how viruses cause diabetes.

Whether Spinoza was referring to reason₁ or reason₂, of course, depends on a broader reading of context and potentially translation. Read alone, it would seem to be reason₁ which is a synonym for explanation:

"If, then, no cause or [explanation] (substitution mine) can be given, which prevents the existence of God, or which destroys his existence, we must certainly conclude that he necessarily does exist."

In this case, Spinoza is casting a wide net for any rationale that might deny the possibility of the existence of God.

Answer 3

Cause and reason are different. Reason, is as you say, a form of cognition whilst cause is generally physical. One reason why they're confused is simply that we say the reason for an effect is the cause.