Sunday [8 October].
Read a few Leaves in Baxters Enquiry into the Nature of the human Soul. He has explaind with great Exactness, the Resistance, which Matter makes to any Change of its State or Condition, whether of motion or of Rest. The Vis Inertiae, the positive Inactivity of matter not barely its Inactivity, but its AntiActivity. For it not only is destitute of a Power of changing its state from Rest to motion or from motion to Rest, but it has the possitive Power, each single Particle has a Possitive Power of Resisting any force that attempts to change its state. But a leaden Ball, held between my fingers, as soon as I withdraw my fingers, will of itself for ought I see change its State from rest to motion and fall suddenly to the floor. This Phenomenon is not Vis Inertiae, ’tis by no Reluctance or Aversion to motion that it moves, but it seems to be a Tendency to motion, an Active Principle. If it is passive the Agent that presses it downwards is invisible. But because matter in all the Experiments I have tried, resists a Change from rest to motion upwards, will it follow, that all matter essentially resists a Change from rest to motion, downwards. Is it a Posteriori from Experiments, that he deduces this Proposition, that all matter essentially resists any Change of State, or is it a Priori from some Property that is essentially included in our Idea of Matter that he demonstratively [argues?] this Vis Inertiae. Is Inactivity, and AntiActivity, included in our Idea of Matter? Are Activity, Perceptivity &c. Properties that we by only comparing Ideas can see to be incompatible to any Properties of matter.
If nothing is Matter which has not this antiactive Principle, then human Minds are not matter for they have no such Principle. We are conscious, that we can begin and end motion of ourselves. If he argues a Posteriori from Experiments, he can pretend only to Probability. For Unless he was certain that he had made the Experiment and found the Property in every Particle of Matter that ever was created, he could not be certain, that there was no Particle in the World, without this Property, tho he had tried all but one and found that they had it. We have tried but a few Parcells of Matter. The Utmost we can say is, that all we have tried are inactive. But for Argument sake I will deny, that all the Parcels that we have tried, have this Property. On the Contrary I will say that all have a motive Power downwards. Powder has an Active Power springing every Way &c. Thus Experiment is turned against the Doctrine. I cant yet see how he will prove all matter Anti inactive a Priori from Properties of matter before known essential, with which he must shew this to be necessarily connected.