The Missing Link in Hume's Account of Causal Reasoning and Causal Belief

Book 1, Part 3:

Section 14. The Idea of Necessary Connection

Para. 1: Custom determines the mind to make a transition from a cause to an effect (or vice versa). The necessity is an impression of reflection.

Para. 4: The circle of equivalents: cause, efficacy, agency, power, force, energy, necessity, connexion, and productive quality.

Paras. 5-11: What is the source of the idea of necessity? Not reason.

Para. 12: Not from analogy to our own will.

Para. 13: Not the necessity of demonstration.

Paras. 15-21: A recapitulation of the account of causal inference.

Para. 22: The source of the idea of necessary connection in a determination of the mind.

Para. 23: The analogy to the necessity of reason.

Para. 26: Objections.

Paras. 28-30: Hume's position restated.

Para. 31: Hume's two definitions of cause.

Para. 32: All causes are efficient causes.

Para. 33: Moral and physical necessity are the same. (What about logical necessity?)

Section 15. Normative Hume's Rules to Judge of Causes and Effects

1. Contiguity in space and time

2. Temporal priority.

3. Constant conjunction.

4. Same cause, same effect.

5. Like effects imply(?) like causes.

6. Different effects must be due to differences in causes.

7. In some cases, but not all, increases and diminutions in causes produce corresponding increases and diminutions in effects.

8. A time separation between a purported cause and an effect shows that the first is not the sole cause of the effect. [This is a corollary of #1.]

Sect. 16: On the reason of animals

What kind of reasoning do beasts exhibit? Do they need the faculty of Reason to do it?

Do beasts have knowledge? Do they have probable belief?

What does Hume mean by "instinct of animals"? How does animal instinct confirm Hume's view that belief in cause and effects does not involve Reason?