Propositions 31 to 49

Part 2= Common ideas

31. We can only have a very inadequate knowledge of the duration of particular things external to ourselves.

Corollary

Hence it follows that all particular things are contingent and perishable.

32. All ideas, in so far as they are referred to God, are true. Proof= All ideas which are in God agree in every respect with their objects (2.7. Coroll.), therefore (1. Ax. 6) they are all true. Q.E.D.

33. There is nothing positive in ideas, which causes them to be called false.

34. Every idea, which in us is absolute or adequate and perfect, is true.

35. Falsity consists in the privation of knowledge, which inadequate, fragmentary, or confused ideas involve.

36. Inadequate and confused ideas follow by the same necessity, as adequate or clear and distinct ideas.

37. That which is common to all (cf. Lemma 2, above), and which is equally in a part and in the whole, does not constitute the essence of any particular thing.

38. Those things, which are common to all, and which are equally in a part and in the whole, cannot be conceived except adequately.

Corollary= It follows that there are certain ideas or notions common to all men.

39. That, which is common to and a property of the human body and such other bodies as are wont to affect the human body, and which is present equally in each part of either, or in the whole, will be represented by an adequate idea in the mind.

Corollary= Hence it follows that the mind is fitted to perceive adequately more things, in proportion as its body has more in common with other bodies.

40. Ideas that spring from adequate ideas in the human mind are also adequate themselves.

41. Knowledge of the first kind is the only source of falsehood.

42. Knowledge of the second and third kinds teaches us to distinguish the true from the false.

43. A person who has a true idea simultaneously= knows that he has a true idea, and cannot doubt of the truth of the thing perceived.

44. It is not in the nature of reason to regard things as contingent, but as necessary.

Corollary 1= It follows that it is only through our imagination that we consider things, whether in respect to the future or the past, as contingent. Note= I will briefly explain how this way of looking at things arises.

Corollary 2= It is in the nature of reason to perceive things under a certain form of eternity (sub quâdam æternitatis specie). Proof= It is in the nature of reason to regard things, not as contingent, but as necessary (2.44).

45. Every idea of every body, or of every particular thing actually existing, necessarily involves God’s eternal and infinite essence.

46. The knowledge of the eternal and infinite essence of God which every idea involves is adequate and perfect.

47. The human mind has an adequate knowledge of the eternal and infinite essence of God.

48. In the mind there is no absolute or free will. But the mind is determined to wish this or that by a cause, which has also been determined by another cause, and this last by another cause, and so on to infinity.

49. There is no volition or affirmation and negation in the mind, save that which an idea, as it is an idea, involves.

Corollary= Will and understanding are one and the same.