Descartes, Boyle, and Le Grand on forms

In the last step, you have read three exerpts from authors criticising the notion of form. Here, we will see in some detail on what grounds these authors criticised the notion of form. Also, we will see that according to one of them, Boyle, the word form could be retained, provided it be interpreted in a very specific way.

Descartes on forms

Consider again the following passage from Descartes’s letter to Regius:

Substantial forms were introduced by the philosophers only in order to account for the proper actions of natural things, of which forms were supposed to be the principles and roots. … But the natural actions of things cannot be explained by such substantial forms, as even their defenders admit that they do not understand what they are. So if they say that some action proceeds from a substantial form, it is as if they said that it proceeds from something they do not understand, and that explains nothing. Therefore, these forms must not be introduced in any way to account for the causes of the natural actions of things.

Boyle on forms

I shall for brevity’s sake retain the word Form, yet I would be understood to mean by it, not a Real Substance distinct from Matter, but only the Matter itself of a Natural Body, considered with its peculiar manner of Existence … For [this] is sufficient to perform the [tasks] that are necessarily required in what Men call a Form, since it makes the Body such as it is, making it appertain to this or that Determinate Species of Bodies, and discriminating it from all other Species of Bodies whatsoever.

Le Grand on forms

This may also be proved another way. For Substantial Forms were only invented by the [Aristotelians], to make out the Causes of all Actions, that are found in Natural Things, whereof they are the Principles, from whence they do proceed: But these Forms are of no use to the explaining of all these effects; seeing that they themselves own them to be hidden … Wherefore when they say that some Action proceeds from Substantial Forms, they may well be reproached for having recourse to a Principle of Actions, the nature whereof they do not conceive, and by consequence neither can any thing of certainty be gather’d from it: Which alone, in my Judgment, is sufficient to reject them altogether, forasmuch as nothing is to be admitted in Philosophy, which is not clearly and distinctly perceived and known. For what can be more unworthy of a Philosopher, than to make those the Principles of Bodily Things, which he can neither explain by Definition, nor demonstrate by Experience, nor conceive in his Mind?

Would you take him for a Philosopher, who being asked about the Nature of Fire and Water, should tell you that Fire is Fire, and Water, Water? For is it not much the same thing, to say that Fire and Water are such by their Substantial Forms? Or would you think him to be an Interpreter of Nature, who being demanded about the Phases, or Appearances of the Moon or Venus, and the Principles of the Stars, would answer, that they proceed from Forms, as from their Inward Principles? What is this but to call all things by one name, and comprehend them under one and the same Notion?

Le Grand here basically repeats the criticism of Descartes. Indeed, Le Grand was a follower of Descartes living in England, and the main goal of his Entire Body of Philosophy was to make Descartes’s philosophy accessible to an English audience.

His criticism is basically that nobody has ever seen a form, or knows precisely what a form is. To say that the physical properties of a body spring from its form, then, is not at all informative. It is to say that the physical properties of a body spring from something unknown.

Le Grand’s own view is that all bodies can be described as machines, whose physical properties follow from the mechanical interaction between, and motion of, their material parts.